Newton's Laws of Motion - Additional Problems I.6.1

A toy truck of mass 7.0 kg is accelerated at 2.5 m/s^{2} along a level floor. What net force is acting on the truck?

A force of 320 N is required to pull a box across the floor at a constant velocity. What is the force of friction between the floor and the box?

A 3 kg ball moves along a horizontal surface at a constant speed of 5.6 m/s.

What net force must be acting on the ball?

If the ball slows down uniformly, coming to a stop in 4.0 s, what net force must have acted on the ball?

What force is necessary to move a 12.0 kg object 150 m along a horizontal frictionless table in 11 s?

If the force acting on an object is doubled, how is acceleration affected?

If the mass of an object is tripled, how is the acceleration affected?

If the force is halved and the mass is doubled, how is acceleration affected?

A 250 kg motorbike is at rest on the street.

Draw a free body diagram for the motorbike.

Describe each of the forces acting on the bike. For each of these forces describe the corresponding reaction force.

A force of 55 N[E] acts on a combination of two boxes that are next to each other on a frictionless surface.
Find:

the acceleration of the boxes.

the force exerted by box A on box B.

the force exerted by box B on box A.

Three toboggans are connected by a rope. The first toboggan has a mass of 75 kg, the second a mass of 55 kg and the third a mass of 10 kg. If the force exerted on the first toboggan is 310 N and surfaces are considered to be frictionless.

Find:

the acceleration of the toboggans

the force exerted by toboggan one on toboggan two.

the force exerted by toboggan two on toboggan three.

Using the following sections of ticker tape, determine if there is a net force on the object.

A man pushes a sofa across the floor at a steady speed of 0.3 m/s. If he has to push with a horizontal force of 500 N, what is the force of friction on the sofa?

more than 500 N

less than 500 N

equal to 500 N

Explain:

For each of the following cases, indicate which of the three laws best explains the situation.

It takes longer for a bus to accelerate from 20 to 100 km/h if it has 50 passengers compared to when it has only 5 passengers.

It hurts when you do a "belly flop" in a swimming pool.

Some hunters have a sore shoulder after firing a shotgun.

Trolley cars provide overhead rails for standing passengers.