Consider a ball at rest in the middle of a wagon. When the wagon is pulled forward the

ball begins to roll against the back of the wagon. Interpret this observation in terms of

Newton’s first Law.

When do you lurch forward in a bus that suddenly slows? Why do you lurch backward when it picks up speed? What law applies here?

Push a shopping cart and it moves. When you stop pushing,

it comes to a rest. Does this violate Newton’s Law of inertia?

When a car moves along the highway at constant velocity, the net force on it is zero. Why, then,

do you continue running your engine?

Roll a bowling ball down a lane and you’ll find it moves slightly

slower with time. Does this violate Newton’s law of inertia?

Consider a pair of forces, one having a magnitude of 20N, and the other is 12N. What maximum net force is possible for these two

forces? What is the minimum new force possible?

As you stand at rest on a floor, does the floor exert an upward force against your feet? If so

what exactly is this force?

A child learns in school that the Earth is traveling faster than

100,000 KM per hour around the sun, and in a frightened tone asks why we aren't swept off. What is

your explanation?

If you toss a coin straight upward while riding a train, where does

this coin land when the motion of the train is uniform along a

straight line track? When the train slows while the coin is in

the air? When the train is turning?

Find the net force produced by a 30 N and 20 N force in each of the following cases:

A: Both forces act in the same direction.B: Both Forces act in the

opposite direction.

What is the net force on a bright red Mercedes convertible

traveling along a straight road at the steady speed of 100 km/hr?

On a long alley a bowling ball slows down as it rolls. Is any horizontal force acting on the

ball? How do you know?

What happens to your weight when your mass increases?

When a junked car is crushed into a compact cube, does its mass change? Its weight? Its

Volume? Explain….

Two basketballs are dropped from a high building through the

air. One ball is hollow and the other filled with rocks. Which accelerates more? Defend your

answer...

Why will a sheet of paper fall slower than one that is wadded

into a ball?

For each of the following interactions, identify action and reaction forces.(a) A hammer hits a nail. (b)Earth gravity pulls down on you. (c ) A helicopter blade pushes air downward.

You hold an apple over your head. (a) Identify all the forces acting on the apple and their

reaction forces. (b) When you drop the apple, identify all the

forces acting on its as it falls and the corresponding reaction

forces.

Identify the action-reaction pairs of forces for the following situations: (a) You step off a curb. (b) You pat your tutor on the back. (c ) A wave hits a rocky shore.

When you drop a rubber ball on the floor it bounces almost to its original height. What causes the

ball to bounce?

If a massive truck and a small sprits car have a head on

collision, upon which vehicle is the impact force greater? Which vehicle experiences the greater

acceleration? Explain….

If you were in a smooth riding bus that is going 50 km/hr and

you flip a coin vertically, what is the horizontal velocity of the coin

in midair?

Suppose you exert a horizontal push on a crate that rests on a

level floor, and it doesn’t move. How much friction acts

compared with your push?

What is meant by the term “Free Fall”?

If the net force is acting on a sliding object triples. What happens to the acceleration?

If the mass of a sliding object triples at the same time the net force on it triples how does the

acceleration compare to its original acceleration?

When only a pair of equal and opposite forces act on an object, what is the net force acting on it?

Which is the most important in winning a tug-o-war;Pulling

harder on the rope, or pushing harder on the floor?

How does a helicopter get its lifting force?