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A student places a ladder up against a wall as shown below. The normal force applied by the wall on the ladder will be directed: down and to the left up and to the right straight up to the left

to the left

A 230 kg steel crate is being pushed along a cement floor. The force of friction is 480 N to the left and the applied force is 1860 N to the right. The forces acting on the crate are __________________. balanced unbalanced

unbalanced

A box sits motionless on a ramp as shown below. The vector arrow for the normal force of the ramp acting on the box will be directed: straight up up and to the left up and to the right down and to the right

up and to the left

As an object falls: both velocity and acceleration increase velocity increases and acceleration decreases velocity increases and acceleration is unchanged

velocity increases and acceleration is unchanged

A rocket blasts off. In 10.0 seconds it is at 10,000 ft, traveling at 3600 mph. Assuming the direction is up, calculate the acceleration. (Hint: the rocket is not under constant acceleration). 5280 ft/s2 528 ft/s2 100 ft/s2 200. ft/s2

528

Which of the following is the most reasonable weight in units of newtons for an average adult? 530 N 120 N 27 N 1000 N

530 N

A caterpillar climbs up a one-meter wall. For every 2 cm it climbs up, it slides down 1 cm. It takes 10 minutes for the caterpillar to climb to the top. Calculate the speed at which the caterpillar travels.

0.5

A force of 6N is exerted on a cart that is carrying a rock and produces an acceleration of 2 m/s2. If the cart has a mass of 1 kg, what is the mass of the rock?

2

A 2,000-kg test car, traveling 60 m/s hits a brick wall. Using motion pictures, the time involved is determined to be 0.050 s. What impulse does the car impart to the wall?

1.2 x 10^5

The weight of an object four earth radii from the center of the earth is: 16 times its weight on the surface its weight on the surface 4 times its weight on the surface 1/16 its weight on the surface

1/16

An object on the surface of the earth weighs 90 lb. At three earth radii above the surface, it will weigh: 90 lb. 10 lb. 30 lb. 270 lb.

10 lb

A 100 N horizontal force is applied to a 5.0 kg box causing the box to move at a constant speed of 3.0 m/s. What is the value of the friction force on the box? 50 N 100 N 115 N 85 N

100 N

A magnetic hockey puck (0.40 kg) hits another hockey puck (0.40 kg) at rest and both travel together to the right at 8.0 m/s. How fast was the first hockey puck initially moving?

16

A train starts from rest and travels for 5.0 s with a uniform acceleration of 1.5 m/s 2. How far does the train travel in this time interval?

19

A skier descends a mountain at an angle of 35.0º to the horizontal. If the mountain is 235 m long, what are the horizontal and vertical components of the skier's displacement? (Use trigonometry to solve.)

193m 135m

An object on earth has a mass of 4 kg. Calculate its weight on another planet that has an acceleration due to gravity one-half that of the earth.

20

An object is thrown directly up (positive direction) with a velocity (vo) of 20.0 m/s and do= 0. How high does it rise (v = 0 cm/s at top of rise). Remember, acceleration is -9.80 m/s2. d = _____ m 1.02 2.04 20.4 40.8

20.4

A 1000-kg car traveling at 66 m/s hits a 2000-kg car at rest and the two travel together after the collision. Calculate the speed with which they move. v = _____ m/s 22 m/s -22 m/s 33 m/s -33 m/s

22

A 230 kg steel crate is being pushed along a cement floor. The force of friction is 480 N to the left and the applied force is 1860 N to the right. What is the normal force? 480 N down 480 N up 2300 N down 2300 N up

2300 N up

A student pushes on a 20.0 kg box with a force of 50 N at an angle of 30° below the horizontal. The box accelerates at a rate of 0.5 m/s2 across a horizontal floor. What is the value of the normal force on the box? 200 N 243 N 156 N 225 N

243 N

A particular grocery bag can withstand 40 N of tension force before it rips. If a shopper places 3 kg of food in the bag, what is the maximum acceleration the bag can withstand before ripping? 3.3 m/sec2 13.3 m/sec2 23.3 m/sec2 40.0 m/sec2

3.3

A 4.0 kg object will have a weight of approximately 14.8 N on Mars. What is the gravitational field strength on Mars? 40 N/kg 3.7 N/kg 1.48 N/kg 0.27 N/kg

3.7

For what reason in Copernican system not entirely correct? Copernicus placed the earth in the center of his system. Copernicus described the orbits of the planets as circular. Copernicus placed the sun at the center of the Universe. Copernicus claimed the earth rotated around the sun but the other planets rotated around the earth.

Copernicus described the orbits of the planets as circular.

"For every action there is an equal and opposite reaction", this statement is

Newton's Third Law

A 6000 kg train car traveling at 2.5 m/s collides with another 6000 kg train car, now they are both moving but with a speed of 1.25 m/s. This is an example of

The Law of Conservation of Momentum

If an object were released in space far away from planets or stars and given an initial momentum (mv), describe what would happen to that object. The object will eventually slow down on its own due to no force being applied to maintain momentum. The object will gradually increase in speed due to the absence of gravity. The object in motion will stay in motion if there are no other forces affecting it. Not enough information is provided to determine the outcome of the experiment.

The object in motion will stay in motion if there are no other forces affecting it.

An elevator is moving in an upwards direction. The free body diagram for the forces acting on the elevator during this time is: The motion of the elevator can best be described as: increasing speed decreasing speed constant speed not enough information to determine the motion

decreasing speed

A baseball is thrown across a field. At a point when the ball has reached its maximum height along its trajectory, the forces that should be included on a free body diagram are: gravity force of throw force of motion there are no forces acting on the ball

gravity

A rope and pulley system is attached to a box (see below). A student pulls on the rope causing the box to accelerate upwards. When drawing the free body diagram for the box, the tension force should be directed: down and to the left up and to the right straight down straight up

straight up

In the picture of a planet in orbit around its star, area A is double that of area B. What is true of the time the planet takes to travel A1A2 as compared to B1B2? It would require time.

twice as much

A 0.2 kg ball moving east at 6 m/s hits a wall and bounces off to the west at 4 m/s. What is the magnitude of the change in momentum of the ball? 2 kg m/s 0.4 kg m/s 1.2 kg m/s 0.8 kg m/s

2 kg

If an object starting from rest and position do = 0 attains a velocity of 20 m/s at d = 50 m, calculate the acceleration required. 4 m/s2 4 m/s 10 m/s 8 m/s2

4 m/s^2

A rocket sled is tested at "5 g" (5 times the acceleration due to gravity). If the sled starts from rest at position do= 0.00, how long does it take to travel 441 meters? t = _____ s 18.0 4.24 9.00 3.00

4.24

What is the approximate weight of a 400 kg object? 4 N 40 N 400 N 4000 N

4000 N

A caterpillar climbs up a one-meter wall. For every 2 cm it climbs up, it slides down 1 cm. It takes 10 minutes for the caterpillar to climb to the top. Calculate the time involved in seconds (not minutes).

600

If a racket strikes a ball (m = 100 g) with a force of 2000 N for 0.3 s., calculate the velocity the ball has as it leaves the racket, assuming it starts from rest. v = _____ m/s 6 m/s 60 m/s 600 m/s 6000 m/s

6000

According to the diagram shown below, the object is: moving at a constant speed accelerating to the right accelerating to the left accelerating down and to the right

accelerating to the right

Why does the momentum before a collision equal the momentum after a collision? because velocity is conserved because force times mass equals acceleration because momentum is conserved

because momentum is conserved

A student stands on a motionless box. When drawing the free body diagram for the box, the normal force vector arrow should be drawn the gravity vector arrow.

larger than

A car travels 30 km north in 25 min. and 40 km east in 35 min. What is the total time in hours? Be careful to carry over the proper number of significant figures when you convert to hours. 0.1 h 1 h 1.0 h 1.00 h

1 h

A student pushes a 12.0 kg box with a horizontal force of 20 N. The friction force on the box is 9.0 N. Which of the following is the best approximation of the box's acceleration? 120 m/s2 20 m/s2 1 m/s2 9 m/s2

1 m/s

A penny falls from a windowsill which is 25.0 m above the sidewalk. How much time does a passerby on the sidewalk below have to move out of the way before the penny hits the ground?

2.26

A 2,000-kg test car, traveling 60 m/s hits a brick wall. Using motion pictures, the time involved is determined to be 0.050 s. What is the magnitude of the force that the car exerts on the wall?

2.4 x 10^6

If Mars takes 1.88 years to rotate around the sun at an average distance of 1.52 au, determine the period for an unknown planet that is 42.0 au from the sun. 51.9 years 273 years 34.7 years 12.1 years

273

A caterpillar climbs up a one-meter wall. For every 2 cm it climbs up, it slides down 1 cm. It takes 10 minutes for the caterpillar to climb to the top. What is the distance traveled? (Round the number to the nearest hundred.)

300

What is the weight of a 30.0 kg object? 3.0 N 300 N 6.8 N 132 N

300 N

A 2.0-kg object moves in a circle of 0.50 m radius at 3.0 m/s. Calculate the centripetal force. 2.4 N 3.6 N 12 N 36 N

36 N

The moon's surface gravity is one-sixth that of the earth. Calculate the weight on the moon of an object that has a mass of 24 kg.

39

A 10.0 kg crate is pushed with a horizontal force of 40 N. The crate moves at a constant velocity of 3.0 m/s. What is the value of the friction force on the crate? 10 N 100 N 40 N 70 N

40

City B is northwest of City A and the 400 mile trip by car takes 8 hours. City B is exactly 320 miles NW of City A if able to travel in a straight line. What is the velocity of the car? 0 mph N 40 mph NW 50 mph NW 80 mph NE

40

A penny is dropped into a well. It takes 5 seconds to fall. Calculate the depth of the well in feet.

400

If a car travels 30.0 mi. north for 30.0 min., 50.0 mi. east for 1.00 hour, and 30.0 mi. south for 30.0 min., what is the average speed of the car over the total trip? 55 mph 55.0 mph 60.0 mph 60. mph

55.0

A force is exerted on a 4.0-kg mass producing an acceleration of 3.0 m/s2. If the mass were changed to 2 kg, the same force would produce how much acceleration on the object?

6

If a car travels 30 mi. north for 30 min., 60 mi. east for 1.0 hour, and 30 mi. south for 30 min., what is the average speed of the car over the first two legs of the trip? 60 mph 50. mph 53 mph 53.3 mph

60

If the car went 30 km west in 25 min. and then 40 km south in 35 min., what would be its average speed? 70 km/h 50 km/h 0.1 km/h 0.14 km/h

70

A car travels 30 km north in 25 min. and 40 km east in 35 min. What is the total distance traveled? 10 km 50 km 70 km cannot be determined

70km

Planet A takes 1 year to go around its star at an average of 1 A.U. distance. Planet B is 4 A.U. from the star. Calculate how long Planet B takes to orbit. ______________ years 512 64 23 8

8

A 70 kg person standing in an elevator is accelerated upwards at a rate of 2.5 m/s2. What is the force of the elevator on the person? 770 N 250 N 875 N -525 N

875 N

Select three different examples of accelerated motion. a body traveling in a straight line and increasing in speed a body traveling in a straight line and decreasing in speed a body traveling in a straight line at constant speed a body standing still a body traveling at a constant speed and changing direction

a body traveling in a straight line and increasing in speed a body traveling in a straight line and decreasing in speed a body traveling at a constant speed and changing direction

A brick moves across a rough surface at constant velocity. Which of the following are forces that should be included in a free body diagram? (select all that apply) gravity friction applied force force of motion

gravity friction applied force

A student gives a brief push to a block of dry ice. A moment later, the block moves across a very smooth surface at a constant speed. When drawing the free body diagram for the block of dry ice moving at a constant speed, the forces that should be included are: (select all that apply) gravity force of push force of friction normal force

gravity normal force

A 2,000-kg test car, traveling 60 m/s hits a brick wall. Using motion pictures, the time involved is determined to be 0.050 s. What is the change in momentum of the car?

-1.2 x 10^5

A car going 72.0 km/h (20.0 m/s) slows down to 36.0 km/h (10.0 m/s) in 5.00 seconds. Calculate the acceleration in m/s2. _____ m/s2 -2.00 -7.00 -30.0 -60.0

-2.00

A penny falls from a windowsill 25.0 m above the sidewalk. How fast is the penny moving when it strikes the ground? (Remember that the velocity will be negative due to the downward motion of the penny)

-22.1

When a car screeches to a sudden stop to avoid hitting a dog, it slows down from 9.00 m/s to 0.00 m/s in 1.50 s. Find the average acceleration of the car.

-6.00

An object is dropped from a platform 100 feet high. Ignoring wind resistance, how long will it take to reach the ground? _____ s 1.8 2.5 3.2 4.5

2.5

A student pushes on a 20.0 kg box with a force of 50 N at an angle of 30° below the horizontal. The box accelerates at a rate of 0.5 m/s2. What is the value of the friction force on the box? 200 N 50 N 43 N 33 N

33 N

To reach city A, you travel north for 2.00 hours covering 80.0 miles. You then turn due east and travel 45.0 minutes for another 20.0 miles to reach your destination. On the first leg of your trip (traveling north), what is your speed? 0 mph 80 mph 80.0 mph 40.0 mph

40.0

Calculate the mass of an object if a force of 20 N produces an acceleration of 4 m/s2. _______ kg 80 0.2 5 20

5

A baseball player swings at a baseball of m = 0.23 kg. The force exerted on the ball by the bat is 5.0 N forward. What is the force of the ball on the bat? 22 N backwards 22 N forwards 5 N forwards 5 N backwards

5 N backwards

City B is northwest of City A, and the 400 mile trip by car takes 8 hours. The cities are 320 miles apart if able to travel in a straight line. What is the speed of a trip from City A to City B? 0 mph 40 mph 50 mph 80 mph

50

A 3.0 kg box is suspended by a series of ropes as shown below. The tension force in the horizontal rope is -40 N. What is the tension force in the rope attached to the ceiling? 40 N 30 N 60 N 50 N

50 N

A 230 kg steel crate is being pushed along a cement floor. The force of friction is 480 N to the left and the applied force is 1860 N to the right. What is the acceleration of the crate? (Hint: remember to find net force first)

6.0

A train starts from rest and travels for 5.0 s with a uniform acceleration of 1.5 m/s2. What is the final velocity of the train?

7.5

The earth takes 1 year to revolve around the sun at 1 A.U. distance (an astronomical unit = 93,000,000 miles). If a planet were 4 A.U. from the sun, how many years would it take to make 1 orbit?

8

If the odometer on the car reads 25.0 km at the beginning of a trip and 65.0 km a half hour later, what is the average speed of the car? (Remember significant digits.) 0 km/h 80 km/h 80. km/h 80.0 km/h

80.0

A car turns a corner at 5 mph. If its speed is increased to 15 mph, its centripetal acceleration is: 9 times the original value the original value 3 times the original value the original value

9 times the original value

Rocket engineers use Newton's third law during launch. Identify the action force. Exhaust gases push down on the earth. Rocket travels upward. Earth pushes back on the exhaust gases.

Exhaust gases push down on the Earth

The graph above describes the relationship between the force applied to a spring in order to stretch it a certain length. Formulate an equation that correctly relates force and stretch. Use the variable F for force and l for stretch and include units. F = 100()l F = 100()l + 20m F = 400()l F = 400()l + 20m

F= 400 ()l

If the forces acting on an object cancel out, the object's motion can be: (select all that apply) moving at a constant speed standing still speeding up slowing down

moving at a constant speed standing still

If for every action force an equal and opposite reaction force exists, how can anything ever be accelerated? The action and reaction forces act on different objects, therefore the net force is not always zero. The action force, when accelerating, is greater than the reaction force. The reaction force is not always in the same vector direction as the action force. none of the above

The action and reaction forces act on different objects, therefore the net force is not always zero.

Which of the following discoveries are attributed to Johannes Kepler? Select all that apply. The orbits of the planets are ellipses. The earth is round. Gravitational forces govern planetary motion. All planets move in elliptical orbits with the sun at one focus. A line connecting a planet to the sun sweeps out equal areas in equal time periods.

The orbits of the planets are ellipses A line connecting a planer to the sun sweeps out equal areas in equal time periods

A ball falls through the air at terminal velocity. Which of the following are forces that should be included in a free body diagram? (select all that apply) gravity force of motion air resistance force of fall

gravity air resistance

A rifle is fired and recoils when the bullet leaves the gun. This is an example of Newton's third law. The acceleration of the bullet is

greater than that of the rifle

A car turns a corner at 10 mph. If it were to turn the corner at 30 mph, the centripetal acceleration would be: nine times larger one-third as large three times larger one-ninth as large

nine times larger

A batter swings at a baseball. The action force is the bat hitting the ball with a force of 5N. What is the reaction force? the hitter swinging the bat the pitcher throwing the ball the ball going away from the bat the ball hitting the bat

the ball hitting the bat

A rifle is fired and recoils when the bullet leaves the gun. This is an example of Newton's third law. The force on the bullet is

the same as that on the rifle

An elevator moves downwards at a constant speed. When drawing the free body diagram for this motion:

the upwards tension force should be drawn the same length as the downwards gravity force

A baseball is thrown to the right. The constant velocity horizontal component of its projectile motion can be explained by drawing the free body diagram so that: there is a large force to the right there is a large force to the left there are equal forces to the right and left there are no forces to the right or left

there are no forces to the right or left

A man and a forklift truck lift equal masses 10 feet vertically. Of the following statements, the correct one is: the man does more work than the forklift the forklift does more work than the man they do the same amount of work insufficient information is given to compare the work done by the man and the forklift

they do the same amount of work