Consider a ball at rest in the middle of a wagon 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 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 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 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 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 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 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 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?