Motion and Forces

A sailboat on a lake sails 40. meters north and then sails 40. meters due east. Compared to its starting position, the new position of the sailboat is

• 40. m due east

• 40. m due north

• 57 m northeast

• 80. m northeast

A ball is thrown straight upward from the surface of Earth. Which statement best describes the ball’s velocity and acceleration at the top of its flight?

• Both velocity and acceleration are zero.

• Velocity is zero and acceleration is nonzero.

• Velocity is nonzero and acceleration is zero.

• Both velocity and acceleration are not zero.

How would the mass and weight of an object on the Moon compare to the mass and weight of the same object on Earth?

• Mass and weight would both be less on the Moon.

• Mass would be the same but its weight would be less on the Moon.

• Mass would be less on the Moon and its weight would be the same.

• Mass and weight would both be the same on the Moon.

As shown in the diagram below, a rope attached to a 500.-kilogram crate is used to exert a force of 45 newtons at an angle of 65 degrees above the horizontal. The horizontal component of the force acting on the crate is

• 19 N

• 210 N

• 41 N

• 450 N

A 40.0-kilogram child exerts a 100.-newton force on a 50.0-kilogram object. The magnitude of the force that the object exerts on the child is

• 0.0 N

• 80.0 N

• 100. N

• 125 N

A student is standing in an elevator that travels from the first floor to the tenth floor of a building. The student exerts the greatest force on the floor of the elevator when the elevator is

• accelerating upward as it leaves the first floor

• slowing down as it approaches the tenth floor

• moving upward at constant speed

• at rest on the first floor

At the bottom of a hill, a car has an initial velocity of +16.0 meters per second. The car is uniformly accelerated at −2.20 meters per second squared for 5.00 seconds as it moves up the hill. How far does the car travel during this 5.00-second interval?

• 107 m

• 74.5 m

• 52.5 m

• 25.0 m

As represented in the diagram, an object of mass m, located on the surface of the Moon, is attracted to the Moon with a gravitational force, F. An object of mass 2m, at an altitude equal to the Moon’s radius, r, above the surface of the Moon, is attracted to the Moon with a gravitational force of

•  $F$  
  

•  $2F$  

•  $\frac{F}{2}$  

•  $\frac{F}{4}$  

The graph represents the relationship between velocity and time for an object moving along a straight line. What is the magnitude of the object’s acceleration?

• 5.0 m/s²

• 10. m/s²

• 8.0 m/s²

• 20. m/s²

A projectile lands at the same height from which it was launched. Which initial velocity will result in the greatest horizontal displacement of the projectile? [Neglect friction.]

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