Force

If an object moves with a constant velocity, we can conclude that ....

• it is moving toward

• there are no forces acting on it.

• there is balanced force act on it

• there are no forces acting on it or there is balanced force act on it

What is the mass of a cart that has an acceleration of 5 m/s/s when a net force of 2000 N is applied to it?

• 10,000 kg

• 2000 kg

• 400 kg

• 1000 kg

The same net force is applied to object A and object B. The observed accelerations of the two objects are not the same; object A has an acceleration three times that of object B. Which of the following is correct?

• Object A has three times the mass of object B.

• Object A has one-third the mass of object B.

• Object A has a different, less streamlined shape than object B

• Object A has more friction than object B.

A ball with a weight of 20 N is thrown vertically upward. What is the acceleration of the ball just as it reaches the top of its path?

• zero

• The acceleration cannot be determined

• 10 m/s/s upward

• 10 m/s/s downward

A 40-kg crate is being pushed across a horizontal floor. If the coefficient of sliding friction is 0.4, what is the frictional force acting on the crate?

• 16 N

• 100 N

• 40 N

• 160 N

If F1 is the force exerted on a cart by a horse and F2 is the force exerted on the horse by the cart, then F1 is _____ F2.

• much greater than

• slightly greater than

• equal to

• slightly less than

A ball with a weight of 40 N is falling freely toward the surface of the moon. What force does this ball exert on the moon?

• zero

• 40 N down

• 40 N up

• We are not able to say

A rocket of mass 2000kg produces a thrust of 3x105 N from its engines during takeoff. Calculate the acceleration of the rocket.

• 150 m/s2

• 60 m/s2

• 40 m/s2

• 240 m/s2

The greater the mass of an object,

• the easier the object starts moving.

• the greater its inertia

• the more balanced it is.

• the more space it takes up.

A child stands on a bathroom scale while riding in an elevator. The child's weight when the elevator is not moving is 100 pounds. What does the scale read when the elevator accelerates upward while traveling downward?

• greater than 100 lbs

• less than 100 lbs

• equal to 100 lbs

• Not enough information is given to answer the question.