Physics Answers

4. A nylon rope used by mountaineers elongates 1.10 m under the weight of a 65.0-kg climber. If the rope is 45.0 m in length and 7.0 mm in diameter, what is Young's modulus for nylon?

3. A circular steel wire 2.00 m long must stretch no more than 0.25 cm when a tensile force of 400 N is applied to each end of the wire. What minimum diameter is required for the wire?

1. A 0.120-kg, 50.0-cm-long uniform bar has a small 0.055-kg mass glued to its left end and a small 0.110-kg mass glued to the other end. The two small masses can each be treated as point masses. You want to balance this system horizontally on a fulcrum placed just under its center of gravity. How far from the left end should the fulcrum be placed?

A large turntable rotates about a fixed vertical axis (hum1200 kg/m²) making 1 revolution in 6.0 s. A 40-kg student initially standing at the center of the turntable, nuns out along a radius. What is the angular speed of the turntable when he is 2.0m from the center?

A hollow, spherical shell with mass 2.00 kg rolls without slipping down at 38.0 slope. Find the acceleration, the friction force, and the minimum coefficient of friction needed to prevent slipping

A baseball leaves the bat at an angle of 37° above the horizontal at a speed of 120 ft/s. How high does it go? How far forward is it at its highest point?

A fan blade is initially rotating an angular speed of 4.6 rpm. It slows down and eventually comes to rest in a time of 32 seconds after turning through a total of 8.8 revolutions. Find

a) the angular speed in rad/s

b) the average angular velocity and

c) the average angular acceleration of the fan blade.

a normal force of 35 N acts over an area of 12.5cm² what is the pressure exerted by the force?

1. A motorcycle begins driving from at rest position. It accelerates at 8 km/hr2 for 20 seconds, then travels at a steady speed for another 20 seconds, all in the same direction. How much distance has it covered since it started driving?

2. An object is dropped from a cliff, the time it takes to hit the ground is 3 seconds. What is the height of the cliff? What is the velocity of the object before it hits the ground?

You are thrown from a motorcycle and skid in a straight line to a complete stop on a rough

gravel path. A measurement of the bloody skidmark reveals that it is 11 m long. What is

the average force did the gravel exert on your body? Assume that your mass is 55.0 Kg

and your initial speed was 30 km/h.