Physics 1210 Final

For an action force, there must be a reaction force that

is exactly equal in magnitude

A 4 kg ball has a momentum of 12 kg m/s. What is the ball's speed?

3 m/s

If a rocket initially at rest accelerates at a rate of 50 m/s^2 for one minute, its speed will be

3000 m/s

What is the force of gravity on a 500 newton woman standing on the Earth's surface?

500 N

A 10 N falling object encounters 4 N of air resistance. The net force on the object is

6 N

If a car accelerates from rest at 2 meters per second, its speed 3 seconds later will be about

6 m/s

During an eclipse of the sun the Hugh ocean tides on Earth are

Extra high

Planets would crash into the sun if it weren't for

Their tangential velocities

Atoms heavier than helium were made by

Thermonuclear fusion

If you push an object twice as far while applying the same force, you do

Twice as much work

Which of these atoms has the most mass

Uranium

Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to

follow a straight line path

The newton is a unit of

force

An Earth satellite is simply a projectile

freely falling around the Earth

An object is propelled along a straight-line path in space by a force. If the mass of the object somehow becomes twice as much, its acceleration

halves

Two objects move toward each other because of gravity. As the objects get closer and closer, the acceleration of each

increases

In each second of fall, the distance a freely falling object will fall is

increasing

A car moves 4 times as fast as another identical car. Compared to the slower car, the faster car has

16 times the KE

If the mass of an object does not change, a constant net fore on the object produces constant

acceleration

Hang from a pair of gym rings and the upward support forces of the rings will always

add up to equal your weight

No force due to Earth's gravity is acting on the astronauts inside the orbiting space shuttle. This statement is

Always false

When properly used, a hydraulic press, like a wheel and axle, is capable of multiplying force input.

Always true

Nuclei of atoms that make up a newborn baby were made in

Ancient stars

The power required to exert 1 N force, over a distance of 1 m in 1 second is

1 W

The air in this room has

all of these

A hydraulic press, like and inclined plane, is capable of increasing energy

always false

Inside a freely falling elevator, there would be no

apparent weight for you

Inside a freely falling runaway elevator, your

apparent weight is zero

Eratosthenes learned about the position of the sun on June 22 by

consulting library information

What makes and element distinct?

the number of protons

A "weightless" astronaut in an orbiting shuttle is

Like the shuttle, pulled by Earth's gravitation

Which of the following is not a vector quantity?

Speed

The smallest particle of those listed below is

a quark

If the sun were twice as massive

both of these

A bullet is dropped into a river from a very high bridge. At the same time, another bullet is fired from a gun, straight down towards the water. Neglecting air resistance, the acceleration just before striking the water

is the same for each bullet

A rifle recoils while firing a bullet. The speed of the rifle's recoil is small because the

rifle has much more madd than the bullet

A projectile is fired vertically from the surface of the Earth at 8 km/s. The projectile will

rise and fall back to the Earth's surface

Two factors that greatly affect air resistance on falling objects are the

size and speed of the object

An asteroid exerts a 360 N gravitational force on a nearby spacecraft. The force is directed

toward the asteroid

An apple falls from a tree and hits the ground 5 meters below. It hits the ground with a speed of about

10 m/s

If a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by about

10 m/s

If the Earth's mass decreased to one half its original mass with no change in radius, then your weight would

decrease to one half your original weight

A bullet fired horizontally over level ground hits the ground in 0.5 second. If it had been fired with twice the speed in the same direction, it would have hit the ground in

0.5s

A 1-kg chunk of putty moving at 1 m/s collides with and sticks to a 5-kg bowling ball that is initially at rest on a frictionless surface. The speed of the putty thereafter is

1/6 m/s

A 10 kg brick and a 1 kg book are dropped in a vacuum. The force of gravity on the 10 kg brick is

10 times as much

A machine puts out 100 watts for every 1000 watts put into it. The efficiency of the machine is

10%

A gun with a muzzle velocity of 100 m/s is fired horizontally from a tower. Neglecting air resistance, how far downrange will the bullet be 1 second later

100

The force of friction on a sliding object is 10N. The applied force needed to maintain a constant velocity is

10N

An airplane that flies at 100 km/h in a 100 km/h hurricane crosswind has a ground speed of

141 km/h

A jumbo jet has a mass of 100,000 kg. The thrust for each of its four engines is 50,000 N. What is the jet's acceleration in meters per second when taking off?

2

Do 100 J of work in 50s and your power output is

2 w

A horse gallops a distance of 10 kilometers in a time of 30 minutes. Its average speed is

20 km/h

A car traveling at 22 m/s comes to an abrupt halt in 0.1 second when it hits a tree. What is the deceleration in meters per second of the car?

220

A bow is drawn so that it has 40 J of potential energy. When fired, the arrow will ideally have a kinetic energy that is

40 J

A man weighing 800 N stands at rest on two bathroom scales so that his weight is distributed evenly over both scales. The reading on each scale is

400 N

A stone is thrown horizontally from the top of a cliff. One second after it has left your hand, its vertical distance below the tip of the cliff is

5 m

A 2kg mass is held 4 m above the ground. What is the approximate potential energy of the mass with respect to the ground?

80 J

A rock is thrown vertically into the air. At the tip of its path, its acceleration in meters per second is

9.8

After rolling halfway down an incline, a marble's kinetic energy is

A same as its potential energy

Disregarding air resistance, objects fall with constant

Acceleration

Which of the following is not a compound?

Air

Suppose a particle is being accelerated through space by a 10 N force. Suddenly the particle encounters a second force of 10 N in the opposite direction from the first force. The particle with both forces acting on it

Continues at the speed it had when it encountered the second force

Padded dashboards in cars are safer in an accident than nonpaodded ones because an occupant hitting the dash has

Increased time of impact

Suppose the moon had twice as much mass as it now does and still orbited the Earth at the same distance. In that case, the ocean bulges on Earth would be

Larger

A rock is thrown upward at 50 degrees with respect to the horizontal. As it rises, neglecting air drag, its horizontal component of velocity

Remains unchanged

A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that

The milk carton has inertia

In science, a theory is

a synthesis of a large body of well tested knowledge

A skydiver of mass 100 kg experiences air resistance of 500 N and an acceleration of

about 0.5 g

A ball player wishes to determine pitching speed by throwing a ball horizontally from an elevation of 5 m above the ground. The player sees the ball land 20 m down range. What is the player's pitching speed?

about 20 m/s

The Doppler effect is characteristics of

all of the above choices

An object in mechanical equilibrium is an object

all of these

Compared to a 1 kg block of solid iron, a 2 kg block of solid iron has twice as much

all of these

Which has zero acceleration? An object

all of these

If no external forces are acting on a moving object, it will

continue moving at the same velocity

A rock is thrown upward at 50 degrees with respect to the horizontal. As it rises neglecting air drag, its vertical component of velocity

decreases

A skydiver jumps from a high flying plane. As her velocity of fall increases, her acceleration

decreases

The two measurements necessary for calculating average speed are

distance and time

A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is

doubled

An object may have potential energy because of its

location

A force is a vector quantity because it has both

magnitude and direction

A kilogram is a measure of an object's

mass

Twelve seconds after starting from rest, an object falling freely will have a speed of

more than 100 m/s

The reason a granite block is mostly empty space is that the atoms in the granite are

mostly empty space themselves

Which of the following are electrically neutral?

neutron

If you push for a half hour or a whole hour against a stationary wall

no work on the wall is done in either case

Starting from rest, the distance a freely falling object will fall in 0.5 second is about

none of the above

A light aluminum ball and a heavy lead ball of the same size are allowed to roll down an incline. When they are halfway down the incline, they will have identical

none of the above choices

Of the sciences known as physics, chemistry, and biology, the most basic is

physics

Which has the greater kinetic energy, a car traveling at 30 km/hr or a car of half the mass traveling at 60 km/hr?

the 60 km/hr

Your weight is

the gravitational attraction force between you and the Earth

Which is most responsible for the ocean tides

the moon

A ball is thrown upwards and returns to the same position. Compared with its original speed after release, its speed when it returns is about

the same

Compared to the mass of a certain object on Earth, the mass of the same object on the moon is

the same

Compared to the atoms that make up the body of an elderly person, the atoms that make up the body of a newborn baby are

the same age

A 1000 kg car and a 2000 kg car are hoisted the same distance. Raising the more massive car requires

twice as much work

How many different elements are in a water molecule

two

If you find that twice as much work is needed to perform a task but it takes twice as much time, the amount of power required is

unchanged

While an object near the Earth's surface is in free fall, its

velocity increases

A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at constant velocity is

zero

When a falling object has reached its terminal velocity, its acceleration is

zero