# Physics

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1)When a car drives off a cliff, why does it rotate forward as it falls? (Consider the torque it experiences as it rolls off the cliff.)
2)The front wheels located far out in front of the racing vehicle help to keep the vehicle from nosing upward when it accelerates. What physics principle is illustrated here?
3)How would a ramp help you to distinguish between two identical looking spheres of the same weight - one solid and the other hollow?

• Physics -

1) After the front wheels have lost contact with the ground, the ground force on the rear wheels applies a torque about the center of mass, causing it to rotate forward.

2) When it accelerates, the ground applies a force to the rear wheels. This results in a backwards-tipping torque about the center of mass. Having wheels and weight far out front helps to counteract this torque and keep front wheels on the ground.

3) A solid sphere has less KE in the form of rotational kinetic energy that a hollow sphere travelinbg at the same velocity. This leaves more of the potential energy conversion available for conversion to translational kinetic energy (and speed). The solid sphere goes faster.