What happens the first time Dr Hewitt lifts the bowling ball near his teeth and lets go?

How is Dr. Hewitt able to break a piece of wood in his demonstration? He moves his hand very quickly.

What happens the first time Dr Hewitt lifts the bowling ball near his teeth and lets go?

Hewitt lifts the bowling ball near his teeth and lets go? All of the initial energy of the ball was converted completely back to potential energy when the ball returned. The ball leaves Dr. Hewitt and returns to him, going past the point where it was released.

When Dr Hewitt cuts the broom right through the center of gravity?

When Dr. Hewitt cuts the broom right through the center of gravity, how do the weights of the two sides of the broom compare? The longer side (the handle) has a greater weight than the bristle side. Both sides of the broom on either side of the center of gravity have equal weight.

Why is a force that is applied for a short time more effective in karate?

Why is a force that is applied for a short time more effective in karate? The average force is increased. Rolling with the punch increases contact time, which decreases the force.

When a boxer is moving away from a punch the force experienced is reduced because?

When a boxer is moving away from a punch, the force experienced is reduced because momentum is reduced.

How much work must the brakes of a car supply to stop a car moving four times as fast?

A four times as fast car has 16 times as much DE and will require 16 times as much work to stop, and 16 times as much stopping distance.

Is it easier to balance a long rod with a mass?

Rotational inertia depends on whether the mass is farther or closer to the point of rotation. The farther the mass is, the higher the rotational inertia. It is easier for the performer to balance a long rod held vertically with people at the other end because the rotational inertia is smaller.

How is a flywheel constructed to maximize?

Rotational speed is constant. The tangential speed on the outer edge of a rotating carousel is _______. How is a flywheel constructed to maximize its rotational inertia? The solid disk will because the mass is closer to the axis of rotation.

Which is easier to get swinging a baseball bat held at the end or one held closer to the massive end choked up )?

Which is easier to get swinging, a baseball bat held at the end or one held closer to the massive end (choked up)? The center of mass and gravity for a baseball bat are closer to the bat head where there is more mass.

Why does a typical small helicopter with a single main rotor have a second small rotor on its tail?

Why does a typical small helicopter with a single main rotor have a second small rotor on its tail? Without the small rotor on its tail, the helicopter and the main rotor would rotate in opposite directions. The small rotor provides a torque to offset the rotational motion that the helicopter would otherwise have.

Why do gymnasts use floor mats that are very thick?

Why do gymnasts use floor mats that are very thick? Because the cushion in the mat extends the time and lessens the force. the steel cord will stretch only a little, resulting in a short time of stop and a corresponding large force.

Which designates a force and which is force multiplied by time?

1 Impact designates a force while impulse is force multiplied by time. Impact designates a force while impulse is force multiplied by time. If the time of impact in a collision is extended by three times, by what factor does the force of impact change?

Does a bullet have more momentum than a moving ship?

The huge ship moves at less than 50 mph, the bullet would have to be propelled at millions of times that velocity to have the same momentum as the ship.

When a ball falls downward it may have a net force?

When a ball falls downward, it may have a net force: of zero.

When you jump from an elevated position?

When you jump from an elevated position you usually bend your knees upon reaching the ground. By doing this, you make the time of the impact about 10 times as great as for a stiff-legged landing. In this way the average force your body experiences is A) less than 1/10 as great. B) more than 1/10 as great.

How many times more work is required to stop the car now that it is going twice as fast?

Note that the speed is squared, so if the speed of an object is doubled, its kinetic energy is quadrupled (22 4). Consequently, it takes four times the work to double the speed. Also, an object moving twice as fast takes four times as much work to stop.

Can a machine multiply input force?

A machine can multiply force and it can multiply distance.

However, it cannot multiply input energy because this would violate the law of conservation of energy.

Which requires more work lifting a 50 kg sack?

Which requires more work- lifting a 50-kg sack a vertical distance of 2 m or lifting a 25-kg sack a vertical distance or 4 m? Both are the same amount of work because the force x distance is the same for each.