Physical Science Exam 1

I throw a ball into the air with a velocity of 20m/s. At the top if its path the ball has how much kinetic energy? 200J 100J 0J -10J

0J

What is the net force acting on a 1000N object traveling a terminal velocity? not enough info 0N 10N 1000N

0N

Stephanie walks around a 400m track. After completing one lap her displacement is 400m 0m not enough info

0m

A ball is tossed vertically into the air. When the ball reaches its highest point, the acceleration of the ball is 0m/s 10m/s/s upward 10m/s/s downward not enough information to determine.

0m/s

What is the acceleration of a 50N object traveling at terminal velocity 0m/s/s 50m/s/s 10m/s/s -10m/s/s

0m/s/s

What is the acceleration of a car that maintains a constant velocity of 100 m/s for 10 s? 0m/s/s 10m/s/s 1000m/s/s 100m/s/s

0m/s/s

When an object is travelling at terminal velocity, what is the objects acceleration? A) 0m/s/s B) 10m/s/s downward C) 10m/s/s upward

A) 0m/s/s

A simple machine can not A)Require less work. B)Decrease the force needed to move an object. C)Increase the distance needed to move an object.

A)Require less work.

Which direction does a table push a book resting on it? UP Down it does not exert a force

UP

When an object is in equilibrium, the net force acting on it is a) 0 b) positive c) negative d) changing

a) 0

. After a rock that is thrown straight up reaches the top of its path and is starting to fall back down, its vertical acceleration is (neglecting air resistance) __________. a) 10m/s/s downward b) less than 10m/s/s downward c) more than 10m/s/s downward

a) 10m/s/s downward

A 500N woman sits at rest on the floor, the floor exerts a reaction force on her of a) 500N b) 5N c) 250N d) 1000N

a) 500N

A block is dragged at constant velocity in a straight line path across a level surface with a force of 6N. What is the frictional force between the block and the surface a) 6N b)less than 6N c) more than 6N

a) 6N

Friction is a force that always acts____________. a) in the same direction as the object's motion b) opposite to the object's motion c) perpendicular to the object motion

a) in the same direction as the object's motion

What term is defined as an object's tendency to continue its current state of motion? (An object at rest wants to stay at rest while and object in motion wants to continue moving at constant velocity.) a) inertia b) velocity c) force d) acceleration

a) inertia

ow does the acceleration of an object change with relation to its mass? a) inversely proportional b) no relationship at all c) directly proportional

a) inversely proportional

when you look at the speedometer in a moving car, you are seeing the car's: a. Instantaneous speed b. Average velocity c. Instantaneous acceleration d. Average distance traveled e. Displacement

a. Instantaneous speed

The reaction force to my foot pushing backward on the floor is a. the floor pushes forward on my foot with equal force b. the floor pushes upward on my foot with equal force c. the floor pushes forward on my foot with more force d. the floor pushes backward on my foot with more force.

a. the floor pushes forward on my foot with equal force

A car travles a distane of 20km with a speed of 60km/hr. How long in hours does it take the car to complete this trip? 3hrs 120hrs 60hrs .33hrs

.33hrs

A 10kg falling object has 200J of mechanical energy. After it falls another 10m, the mechanical energy changes by 0J reducing 100J adding 100J none of the above

0J

An object falls from a tall building. Half way down the building the object has lost 100J of potential energy. How much kinetic energy has it gained? 0J 100J 50J None of the above

100J

An object that weighs 100N falls out of a plane, how much force is needed upward in order to reach terminal velocity Not enough info 100N 10N 0N

100N

What is the weight of a 10kg object on Earth? 10kg 10N 100N 1N

100N

A penny is dropped from a cell phone tower, after about 2s of free fall the acceleration of the penny is 0m/s 10m/s down 30m/s down

10m/s down

If I travel 300 meters in 25 seconds, what was my average velocity? .083m/s 10m/s 12m/s 75,0000m/s

12m/s

A car has a mass of 1000 kg and accelerates at 2 m/s2. What is the magnitude of the force exerted on the car? 500N 1000N 1500N 2000N

2000N

A 300-kg bear grasping a vertical tree slides down at constant velocity. The friction force between the tree and the bear is 300N 30N 3000N more than 3000N

3000N

A penny is dropped from the top of a cell phone tower. After 3 seconds of free fall, the velocity of the penny is 10m/s down 30m/s down 30m/s up

30m/s down

A ball is tossed into the air with a velocity of 30m/s upward, the thrower catches the ball from the same height it was thrown at. What is the velocity of the ball right before it was caught? 10m/s upward 30m/s downward 30m/s upward 10m/s downward

30m/s downward

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 200N 400N 800N 1600N

400N

An airplane travels at 165 km/hr . How far does the plane travel in a time of 3hrs. 55Km 495km .018km

495km

n object is pulled northward with a force of 10 N and southward with a force of 15 N. The magnitude and direction of the net force on the object is 5N North 5N South 25 N North 25N South

5N South

A 10-N falling object encounters 4 N of air resistance. The magnitude of the net force on the object is 4N 14N 6N 40N

6N

An automobile traveling at 10 km/hr, accelerated to 82 km/hr in 9.0 seconds. What is its acceleration? 8km/hr/s 9km/hr/s 10km/hr/s 82km/hr/s

8km/hr/s

In orbit around the earth, an astronaut's _________ is the same and his _________ is less than what it would be on earth. A. mass, weight B. weight, mass C. weight, force of gravity D. weight, inertia

A. mass, weight

Which of the following describes an object that has to be in equllibrium. An object that has two or more forces are acting on it An object that is accelerating An object that is changing direction An object traveling at a constant velocity

An object traveling at a constant velocity

. A ball is dropped from some height, h. Pictures were taken at every second. Which of these diagrams best describes the ball's motion as it continues to fall?

B

A 20kg shopping cart moving at a velocity of 0.5m/s collides with a store wall and stops. The momentum of the shopping cart A) increases B) decreases C) remains the same

B) decreases

A roller coaster climbs up a hill at 4 m/s and then zips down the hill at 30 m/s. The momentum of the roller coaster A) is greater up the hill than down the hill. B) is greater down the hill than up the hill. C) remains the same throughout the ride. D) is zero throughout the ride.

B) is greater down the hill than up the hill.

Which has more momentum, a large mass moving at 30 miles per hour or a small mass moving at 30 miles per hour? A) small mass B) large mass C) the same for both

B) large mass

A 20 kg cart is pushed with a force of 40 N while it encounters a frictional force of 20 N. What is the cart's acceleration? A. 4 m/s2 B. 1 m/s2 C. 0 m/s2 D. 5 m/s2

B. 1 m/s2

. Which object has more inertia a 1,000 kg car or 10,000 kg truck? A. 1,000 kg car B. 10,000 kg truck C. same inertia for both

B. 10,000 kg truck

A girl does 90 Joules of work in 5 seconds to climb a flight of stairs. What is her power output vertically? A. 180 W B. 18 W C. 9,00 W D. 4,00 W

B. 18 W

Three second after starting from rest, a freely falling object will have a speed of about? A. 10 m/s downward B. 30m/s downward C. 50 m/s downward D. 2.5 m/sdownward

B. 30m/s downward

What is the mass of an object which experiences a constant net force of 40 N while accelerating at 5 m/s2? A. 5 kg B. 8 kg C. 40 kg D. 200 kg

B. 8 kg

. In the "equal and opposite" Newton's Third Law, reaction force to a bat hitting a ball is the _________________. A. bat having a greater force on the ball than the ball has on the bat B. ball putting equal force on the bat C. ball having greater force than the bat D. ball stopping

B. ball putting equal force on the bat

Salik tosses a ball vertically upward. It rises, reaches its highest point, and then falls back into Salik's hand. During this time, the acceleration is always ________________. A. in the upward direction B. in the downward direction C. in the direction opposite its velocity D. in a horizontal direction

B. in the downward direction

An object is moving at a constant speed in a straight line. We can conclude that _____________________. A. there must be an even number of forces acting on it B. the vector sum of all the forces acting on it must be zero C. the object must have a net force. D. there must be a normal force acting on it

B. the vector sum of all the forces acting on it must be zero

What has more mass? 5kg of feathers 5kg of lead Both choices have the same mass.

Both choices have the same mass.

A stunt person jumps from the roof of a tall building, but no injury occurs because the person lands on a large, air-filled bag. Which one of the following best describes why no injury occurs? A) The bag provides the necessary force to stop the person. B) The bag reduces the impulse to the person. C) The bag decreases the amount of time during which the momentum is changing and reduces the average force on the person. D) The bag increases the amount of time during which the momentum is changing and reduces the average force on the person.

C) The bag decreases the amount of time during which the momentum is changing and reduces the average force on the person.

Compared to a sports car moving at 30 miles per hour, the same sports car moving at 60 miles per hour has __________. A) same momentum B)half of the momentum C)double the momentum D)triple the momentum

C)double the momentum

Brendan catches a ball when its velocity is 40 m/s downward. If he catches the ball at exactly the same height from which he threw the ball, what do you think was the ball's initial velocity? A. 0 m/s B. 20 m/s up C. 40 m/s up D. 5 m/s up

C. 40 m/s up

. Which of the following statements is TRUE regarding a 10.0 kg object on the moon where the acceleration due to gravity is 2.0 m/s2? A. Its mass is 5.0 kg B. Its weight is 10 N C. Its weight is 5 N D. Its weight is 20 N

C. Its weight is 5 N

A 100 kg cart accelerates from 5 m/s to 10 m/s. Compare the cart's final kinetic energy to its initial kinetic energy. A. the same B. two times as great C. four times as great D. one-half as great

C. four times as great

An unfortunate bug splatters against the windshield of a moving car. Compared to the force of the car on the bug, the force of the bug on the car is __________. A) smaller. B) larger. C) Need more information to say D) the same.

D) the same.

Two students push on a box. One with a force of 60 N and the other with a force of 80 N; both in the same direction. The magnitude of the force on the box by both students would be __________. A. 20 N B. 70 N C. 100 N D. 140 N

D. 140 N

One car travels 40m due east in 5.0 seconds. What is the cars velocity? A. 8 m/s B. 200 m/s C. 40 m/s east D. 8 m/s east

D. 8 m/s east

Two identical cars, each traveling 20 m/s, are brought to a stop. Car A stops by applying its brakes in a normal way. Car B stops as a result of running into an unmovable concrete wall. Which of the following statements is true? A. Car A has the greatest change in momentum B. Car A experiences the greatest impulse C. Car B has the greatest change in momentum D. Car B has the greatest force applied to it

D. Car B has the greatest force applied to it

Which has a greater effect on the gravatational attraction between two masses? Mass Distance Universal Constant

Distance

Car A and B are identical and are travelling with the sane velocity. Car A comes to a stop over a period of time of 2s, Car B comes to a stop in a much shorter time of .01s. Car A will have the lower change in momentum True False

False

Kinetic friction is always greater than static friction between the same two surfaces True False

False

It does not change It doubles It quadruples it reduces to 1/2

It quadruples

The type of energy that deals with the movement of an object is Kinetic Potential Chemical Elastic

Kinetic

The type of energy that deals with the location of an object is Kinetic Potential Elastic Chemical

Potential

A Mack truck and a Volkswagen traveling at the same speed have a head-on collision. The impact force is greatest on the Volkswagon Truck Same for both

Same for both

All objects of mass are attracted to each other True False

True

Athletes "follow through" when swinging because it helps increase the change of momentum of the ball the are swinging at. True False

True

By bending my knees when jumping from the counter, I decrease the force on my body because I increase the time it takes for me to stop falling. True False

True

Gravitationally speaking you are more attracted to bigger people. True False

True

The force of gravity between you and the Earth depends on, your mass, the Earth's mass and the distance beween you and the center of the Earth True False

True

Which of the following is not a device that can accelerate your car? steering wheel brake pedal gas pedal all of the above answers can accelerate a car

all of the above answers can accelerate a car

A heavy object and a light object are dropped at the same time from rest in a vacuum. The heavier object reaches the ground __. before the lighter object at the same time as the lighter object after the lighter object

at the same time as the lighter object

10N force and a 30N force act in opposite directions. What is the net force on the object a) 10N b) 20N c) 30N d) 25N

b) 20N

When walking forward across the floor, the force of friction acts backward upward downward forward

backward

You weight on Earth is dependent on your mass your distance between the center of the earth and you both A and B None of the above

both A and B

A 10N force and a 30N force act in the same direction on an object. What is the net force on the object a) 30N b) 10N c) 40N d) 25N

c) 40N

Which of the following is the cause of an acceleration a) velocity b) speed c) force d) inertia

c) force

A roller coaster has 5000J of potential energy at the top of a hill, how much kinetic energy will the roller coaster have at the bottom of the hill? a. 0J b. 2500J c. 5000J d. None of the above

c. 5000J

Bob runs up a flight of stairs and then walks up a flight of stairs. In which situation does Bob exert more work? a. running up the stairs b. walking up the stairs c. the same for both

c. the same for both

Assuming no air resistance, if you dropped a penny from a cliff and it fell for 12 seconds, during which second did the penny travel the greatest distance vertically (when did it fall the farthest? a) 1-2 seconds b) 3- 4 sec c) 9-10 sec d) 10-11 sec

d) 10-11 sec

A girl pulls on a 10kg wagon with a constant force of 30N. What is the wagon's acceleration? a) 30m/s/s b) .3m/s/s c) 10m/s/s d) 3.0m/s/s

d) 3.0m/s/s

A box is being pushed across a rough surface with constant velocity, which of the following is true? a) there is not friction acting on the box b) the friction is less than the applied force c) the friction is more than the applied force d) the frictional force is equal to the applied force

d) the frictional force is equal to the applied force

. A skier has 10,000J of potential energy at the top of a hill, how much kinetic energy will the skier have at the bottom of the hill if you ignore friction? a. 4000J b. 6000J c. 8000J d. 10,000J

d. 10,000J

An 10kg object is held at rest 5m above the ground. What is the objects Gravitational Potential Energy a.50J b.500J c. 5000J d. 1J

d. 1J

Potential energy is the energy an object has because of its __________. a. Temperature b. Density c. Position d. Velocity

d. Velocity

. An object that has kinetic energy must be __________. a. at rest b. elevated c. stopped d. moving

d. moving

If an object's mass is decreasing while a constant force is applied to the object, the acceleration increase decreases stays the same

increase

Distance is a quantity that _____. is always a vector quantity. neither a vector or scalar quantity. is always a scalar quantity

is always a scalar quantity

Suppose a lion is in free fall. Each second the lion falls _____. it covers a larger distance than the second before covers the same distance as the second before covers less distance as the second before

it covers a larger distance than the second before

IN order to increase the amount of friction between two surfaces I can make the surfaces more smooth make one of the surfaces start to move make the surfaces more rough

make the surfaces more rough

The force of friction does not depend on the normal force pressing the two surfaces together surface area the bumpiness of the surfaces

surface area

When a person pushes against a floor, the person is propelled forward because the person's legs push forward on the floor the pushing force eliminates the frictional force the floor exerts a force that propels the person forward.

the floor exerts a force that propels the person forward.

When walking across a floor the force of friction depends on how big my foot is how fast I am walking the type of surface I am working on

the type of surface I am working on

25m due East is an example of vector quantity scalar quantity

vector quantity

As an object freely falls, its _____. acceleration increases velocity increases velocity and acceleration increase velocity and acceleration remain the same

velocity increases

When you go to the moon, what changes: weight mass both mass and weight none of the above

weight