physics 6-10

Which of the following quantities are units of momentum? (There could be more than one correct choice.) A) N ∙ m B) kg ∙ s/m C) kg ∙ m/s D) N ∙ s E) kg ∙ m2/s2

kg*m/s N*S

what is SI unit for youngs

kg/m*s2

a rubber ball bounces off wall with initial speed and reverses direction so its speed is v after bounce. after this which quantitity is conserved

kinetic energy

solid sphere and cylinder, both perfect, roll without slipping at same speed, the total KE of the sphere is ...

less than that of the cylinder

two objects of different masses have momentum of equal non zero magnitude, which has more kinetic energy

lighter object

diego moves to the center of merry go round what happens when he does thi

moment of inertia decreases and angular speed increases

person sids freely spinning stool with no friction when she extends her arms..

moment of inertia increase and angular speed decreases

a puck runs into horizontal spring that is fastened on table. the puck compresses bty 15 before coming to rest. during this process what is conserved

the mechanical energy

same forces act for the same length on two different objects, the magnitude of change in momentum for lighter object is....

the same as the larger one

small car meshes with large, which is true about average force during collision

the small car and truck had same force

small uniform disk and sphere are released at the same time which one will reach the bottom first

the sphere

waiter fills water glass with ice water such that the ater is level with glass, as the ice melts

the water remains flush with the rim of glass

you throw a baseball straight up. compare sign of work done by gravity while ball goes up with sign of work done by gravity while it goes down A) The work is positive on the way up and positive on the way down. B) The work is positive on the way up and negative on the way down. C) The work is negative on the way up and positive on the way down. D) The work is negative on the way up and on the way down because gravity is always downward.

the work is negative on the way up and positive on the way down

35 N bucket of water is lifted vertically 3 m and then returned to original position, how much work did gravity do on bucket A) 180 J B) 90 J C) 45 J D) 0 J E) 900 J

0J

2 kg ball move east at 3 collides with and sticks with 4 kg ball at 2. what is magnitude of mometum just after collision

10

A force produces power P by doing work W in a time T. What power will be produced by a force that does six times as much work in half as much time? A) 12P B) 6P C) P

12P

When you drop a pebble from height H, it reaches the ground with kinetic energy K if there is no air resistance. From what height should you drop it so it will reach the ground with twice as much kinetic energy? A) H B) 2H C) 4H D) 8H E) 16H

2H

if alll wires have same diameter which one will stretch the MOST

3.00 m wire

A tiger is running in a straight line. If we double both the mass and speed of the tiger, the magnitude of its momentum will increase by what factor? A) 1 B) 2 C) 4 D) 8 E) 16

4

what is the ratio of volume a to volume b

4/3

When you drop a pebble from height H, it reaches the ground with speed V if there is no air resistance. From what height should you drop it so it will reach the ground with twice speed? A) H B) 2H C) 4H D) 8H E) 16H

4H

if wood replaced by sheet htat has half diameter of original piece what is the new pressure

4p

Which requires more work, increasing a car's speed from 0 mph to 30 mph or from 50 mph to 60 mph? A) 0 mph to 30 mph B) 50 mph to 60 mph C) It is the same in both cases.

50 mph to 60 mph

styrofoam sphere is compressed so radius is r/2. what is density

8p

A heavy dart and a light dart are launched horizontally on a frictionless table by identical ideal springs. Both springs were initially compressed by the same amount. Which of the following statements about these darts are correct? (There could be more than one correct choice.) A) The darts both have the same kinetic energy just as they move free of the spring. B) The lighter dart leaves the spring moving faster than the heavy dart. C) The heavy dart had more initial elastic potential energy than the light dart. D) Both darts move free of the spring with the same speed. E) Both darts had the same initial elastic potential energy

A) The darts both have the same kinetic energy just as they move free of the spring. B) The lighter dart leaves the spring moving faster than the heavy dart. E) Both darts had the same initial elastic potential energy

A rocket explodes into two fragments, one 25 times heavier than the other. The magnitude of the momentum change of the lighter fragment is A) 25 times as great as the momentum change of the heavier fragment. B) The same as the momentum change of the heavier fragment. C) 1/25 as great as the momentum change of the heavier fragment. D) 5 times as great as the momentum change of the heavier fragment. E) 1/4 as great as the momentum change of the heavier fragment.

B) The same as the momentum change of the heavier fragment.

You and your friend, who weighs the same as you, want to go to the top of the Eiffel Tower. Your friend takes the elevator straight up. You decide to walk up the spiral stairway, taking longer to do so. Compare the gravitational potential energy of you and your friend, after you both reach the top. A) It is impossible to tell, since the times you both took are unknown. B) It is impossible to tell, since the distances you both traveled are unknown. C) Your friend's gravitational potential energy is greater than yours, because he got to the top faster. D) Both of you have the same amount of gravitational potential energy at the top. E) Your gravitational potential energy is greater than that of your friend, because you traveled a greater distance in getting to the top.

Both of you have the same amount of gravitational potential energy at the top.

You are standing on a skateboard, initially at rest. A friend throws a very heavy ball towards you. You have two choices about what to do with the ball: either catch the ball or deflect it back toward your friend with the same speed as it was originally thrown. Which choice should you make in order to maximize your speed on the skateboard? A) Catch the ball. B) Deflect the ball back. C) Your final speed on the skateboard will be the same regardless whether you catch the ball or deflect the ball.

Deflect the ball back.

You slam on the brakes of your car in a panic, and skid a certain distance on a straight level road. If you had been traveling twice as fast, what distance would the car have skidded, under the same conditions? A) It would have skidded 4 times farther. B) It would have skidded twice as far. C) It would have skidded 1.4 times farther. D) It would have skidded one half as far. E) It is impossible to tell from the information given.

It would have skidded 4 times farther.

if truck has 4x mas of car and with 2x speed, it is correct to say A) Kt = 16Kc. B) Kt = 4Kc. C) Kt = 2Kc. D) Kt = Kc. E) Kt = Kc.

Kt = 16Kc

Two cyclists who weigh the same and have identical bicycles ride up the same mountain, both starting at the same time. Joe rides straight up the mountain, and Bob rides up the longer road that has a lower grade. Joe gets to the top before Bob. Ignoring friction and wind resistance, which one of the following statements is true? A) The amount of work done by Joe is equal to the amount of work done by Bob, but the average power exerted by Joe is greater than that of Bob. B) The amount of work done by Joe is greater than the amount of work done by Bob, and the average power exerted by Joe is greater than that of Bob. C) Bob and Joe exerted the same amount of work, and the average power of each cyclist was also the same. D) The average power exerted by Bob and Joe was the same, but Joe exerted more work in getting there.

The amount of work done by Joe is equal to the amount of work done by Bob, but the average power exerted by Joe is greater than that of Bob.

the water pressure to an apartment is increased by water company. the water enters apartment through entrance valve at front. where will increase in static water pressure be greatest when no water is flowing from system

it will be same at all faucets

A very elastic rubber ball is dropped from a certain height and hits the floor with a downward speed v. Since it is so elastic, the ball bounces back with the same speed v going upward. Which of the following statements about the bounce are correct? (There could be more than one correct choice.) A) The ball had the same momentum just before and just after the bounce. B) The magnitude of the ball's momentum was the same just before and just after the bounce. C) The ball's momentum was conserved during the bounce. D) None of the above statements are correct

The magnitude of the ball's momentum was the same just before and just after the bounce.

A small car meshes with a large truck in a head-on collision. Which of the following statements concerning the momentum during the collision are correct? (There could be more than one correct choice.) A) The momentum of the truck is conserved. B) The momentum of the car is conserved. C) The car and the truck must undergo the same change in speed. D) The momentum of the car and the momentum of the truck are each conserved. E) The momentum of the car-truck system is conserved, but the momentum of each one separately is not conserved.

The momentum of the car-truck system is conserved, but the momentum of each one separately is not conserved.

A small car meshes with a large truck in a head-on collision. Which of the following statements concerning the magnitude of the momentum change during the collision is correct? (There could be more than one correct choice.) A) The truck experiences the greater magnitude momentum change. B) The small car experiences the greater magnitude momentum change. C) The small car and the truck experience the same magnitude momentum change. D) The magnitude of the momentum change experienced by each one is inversely proportional to its mass. E) The magnitude of the momentum change experienced by each one is directly proportional to its mass.

The small car and the truck experience the same magnitude momentum change.

A person stands on the edge of a cliff. She throws three identical rocks with the same speed. Rock X is thrown vertically upward, rock Y is thrown horizontally, and rock Z is thrown vertically downward. If the ground at the base of the cliff is level, which rock hits the ground with the greatest speed if there is no air resistance? A) Rock X B) Rock Y C) Rock Z D) They all hit the ground with the same speed.

They all hit the ground with the same speed.

A lightweight object and a very heavy object are sliding with equal speeds along a level frictionless surface. They both slide up the same frictionless hill with no air resistance. Which object rises to a greater height? A) The heavy object, because it has greater initial kinetic energy. B) The light object, because gravity slows it down less. C) The lightweight object, because the force of gravity on it is less. D) The heavy object, because it has more mass to carry it up the hill. E) They both slide to exactly the same height.

They both slide to exactly the same height.

what was the reason for long barrell in big bertha guns in ww2

allow force of excpanding gases from gunpowder to act for longer time

tensile stress is

applied force per cross sectional area

two solid balls one R and M, other 2r and 8M roll down which one will reach first

both at same time

person x pushes twice as hard against a stationary brick wall as personY. which one is correct A) Both do positive work, but person X does four times the work of person Y. B) Both do positive work, but person X does twice the work of person Y. C) Both do the same amount of positive work. D) Both do zero work. E) Both do positive work, but person X does one-half the work of person Y.

both do zero work

A 4.0 kg object is moving with speed 2.0 m/s. A 1.0 kg object is moving with speed 4.0 m/s. Both objects encounter the same constant braking force, and are brought to rest. Which object travels the greater distance before stopping? A) the 4.0 kg object B) the 1.0 kg object C) Both objects travel the same distance. D) It cannot be determined from the information given.

both have same

Three cars (car L, car M, and car N) are moving with the same speed and slam on their brakes. The most massive car is car L, and the least massive is car N. If the tires of all three cars have identical coefficients of kinetic friction with the road surface, for which car is the amount of work done by friction in stopping it the greatest? A) The amount of work done by friction is the same for all cars. B) Car L C) Car M D) Car N

car L

which wire would stretch the least if copper is the biggest value

copper

iron sinks to bottom of lake where pressure is 21 times then surface. what happens to volume and density

decreases increases

disk and hoop idential are released at same time, which ones reahces incline first with no slipping

disk

as you are leaving, door opens outward if hinges are on right what is the direction of angular velcoity on door

down

if the force on an object is negative, the work must be.... A) negative. B) positive. C) The work could be either positive or negative, depending on the direction the object moves.

either positive or negative depending on the direction the object moves

in pool, white ball hits 5 and stops. whie 5 moves away iwht same velocity. they have same mass, what is this collision

elastic

an inelastic collision involving isolated system the final total momentum is...

exactly hte same as the initial momentum

If a stone is dropped with an initial gravitational potential energy of 100 J but reaches the ground with a kinetic energy of only 75 J, this is a violation of the principle of conservation of energy. A) True B) False

false

if sum of external torque is zero then sum of external force is zero

false

if sumn of external forces on object is zero, then sum of external torque is zero

false

sum of both external torque and force is zero then obejct is at rest

false

there must be equal amounts of mass on both sides of center of mass of system

false

two same forces applied at doorknob, firtst is perpendicular and second 30 degrees which one exerts greater torque about door hinge

first force applied perpendicular

Jill does twice as much work as Jack does and in half the time. Jill's power output is A) the same as Jack's power output. B) one-fourth as much as Jack's power output. C) one-half as much as Jack's power output. D) twice Jack's power output. E) four times Jack's power output

four times Jack's power output

A stone is held at a height h above the ground. A second stone with four times the mass of the first one is held at the same height. The gravitational potential energy of the second stone compared to that of the first stone is A) one-fourth as much. B) one-half as much. C) twice as much. D) four times as much. E) the same.

four times as much.

Joe and Bill throw identical balls vertically upward. Joe throws his ball with an initial speed twice as high as Bill. If there is no air resistance, the maximum height of Joe's ball will be A) four times that of Bill's ball. B) two times that of Bill's ball. C) equal to that of Bill's ball. D) eight times that of Bill's ball. E) roughly 1.4 times that of Bill's ball.

four times that of Bill's ball

a railroad car collides with and sticks to identical one that is at rest, after the collision the kinetic energy is....

half as much as before

Two objects, one of mass m and the other of mass 2m, are dropped from the top of a building. If there is no air resistance, when they hit the ground A) both will have the same kinetic energy. B) the heavier one will have twice the kinetic energy of the lighter one. C) the heavier one will have four times the kinetic energy of the lighter one. D) the heavier one will have half the kinetic energy of the lighter one. E) the heavier one will have one-fourth the kinetic energy of the lighter one.

heavier one will have 2x more kinetic energy

which is expectred to have smallest bulk modulus

helium vapor

spinning ice skater on smooth ice controls rotating rate with arms, which is true

her angular momentum is constant

The momentum of an isolated system is conserved A) only in inelastic collisions. B) only in elastic collisions. C) in both elastic and inelastic collisions.

in both elastic and inelastic collisions

air bubble underwater has same pressure as that of surroundnign water. as the air bubble rises toward the surface and the temperature is sane, volume will....

increase

Two friends are standing on opposite ends of a canoe that is initially at rest with respect to a frictionless lake. The person in the front throws a very massive ball toward the back, and the person in the back catches it. After the ball is caught, the canoe is A) moving backward. B) stationary. C) moving forward

moving forward

two men push against car stalling, jerry stops ater 10 min, joel does after 15. compare the work A) Joel does 75% more work than Jerry. B) Joel does 50% more work than Jerry. C) Jerry does 50% more work than Joel. D) Joel does 25% more work than Jerry. E) Neither of them does any work.

neither does any

the linear velocity of the sphere at the bottom of the incline depends on..

neither the mass nor the radius of the sphere

if a ping pong ball bounces back west and ball moves slowly to the east after coliding, which has greater impulse during collision

neither they have the same

an egg falls from nest in tre adn feels no effects to air, as it falls....

only mechanical energy is conservved

hollow sphere is filled with liquid so that it sdensity is p. you enlarge sphere so radius is 2r and fill it with same liquid. what is density of enlarged sphere

p

If the units of your answer are kg ∙ m2/s3, which of the following types of quantities could your answer be? (There could be more than one correct choice.) A) kinetic energy B) potential energy C) force D) power E) work

power

one stretchs metal wire, which condition reached first

proportional

sphere rolls without slipping. angluar velocity of sphere at bottom depends on...

radius

tensile strain is

ratio of change in length to original length

which is accurate statement regarding tensile strain and stress

ratio of tensile stress to strain is youngs modulus

two blocks of same material with one 2x volume, which has greater shear

same

two spheres from same metal, one has 2x diameter. which will have greater bulk

same

two wires have same metal but one is twice as long as wire, which will have greatest modulus

same for both

sphere, cylinder and pipe all are indentical. which one will rach the bottom first

sphere

disk, hoop and sphere are all released at same. what order do they reach the bottom

sphere disk hoop

if you want to double kinetic energy what factor must you icnrease momentum

sqrt 2

when car is weight it is drivel on floor over scale, the weight is equal to

sum of both

which one ha more kinetic energy, 500 kg moving at 40m/s or 1000 moving at 20 A) The 500-kg object B) The 1000-kg object C) Both have the same kinetic energy.

the 500

A rubber ball and a lump of clay have equal mass. They are thrown with equal speed against a wall. The ball bounces back with nearly the same speed with which it hit. The clay sticks to the wall. Which one of these objects experiences the greater momentum change? A) the ball B) the clay C) Both of them experience the same non-zero momentum change. D) Both of them experience zero momentum change.

the ball

two forces produce equal torques on door about door hinge, first is applie at midpoint and the other at doorknob, both perpendiocular which has greater

the first at midpoint

two objects of different mass have equal non zero kinetic energies, which object has greater magnitude momentum

the heavier one

Three cars (car F, car G, and car H) are moving with the same speed and slam on their brakes. The most massive car is car F, and the least massive is car H. If the tires of all three cars have identical coefficients of kinetic friction with the road surface, which car travels the longest distance to skid to a stop? A) They all travel the same distance in stopping. B) Car F C) Car G D) Car H

they all have same

the net accelerating force exerted on each of the 3 cars is identical, after 10 seconds which one has most momentum

they all have the same

consider uniform hoops of R and M without slipping but rolling, which is larger, the translational KE or rotiational KE

they are the same

when rigid object rotates about fixed axis wat is true about all points in object

they have same angular speed and acceleration

Two frisky otters slide down frictionless hillsides of the same height but different slopes. The slope of the hill of otter 1 is 30°, while the slope of the hill of otter 2 is 60°. If both start from rest, which otter is moving faster when she reaches the bottom of her hill? A) Otter 1 is moving faster. B) Otter 2 is moving faster. C) The heavier otter is moving faster, no matter which hill she used. D) Both otters have the same speed at the bottom. E) The otter that took the shorter time is moving faster

they have same speed at the bottom

in a collision between two unequal masses which amss receives greater impulse

they have the same

25 kg piece of equipment, if all wires have same diameter which will stretch greatest percentage

they will have same

when you ride bike in what direction is the angular velocity of the wheels

to your left

if firecracker explodes midwair and breaks up, which is true containing conditiones before and after

total momentum of gragments is equal to original momentum of firecracker

solid uniform sphere rolling wihtout slipping. which form of kinetic is larger, translational or rotiation

translational

consider a brick is totally immersed in water, with long edge of brick vertical. the pressure is...

trhe greatest on the bottom

if object is at rest then the sum of external torque and force is zero

true

when is angular momentum of system constant

when no net external torque acts on system