A pulley block and tackle is used to lift a piano. The piano weighs 2000N. If the worker used 100 N of force to lift the piano, what is the mechanical advantage of the block and tackle?

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Which of the following processes add methane (CH4) to the atmosphere? A. Breakdown of plant and animal remains in the soil. B. Leakage from natural gas pipelines. C. Food digestion by land animals. D. All of the above.

Why are water molecules polar?

Coin-shaped compartment that contains light-absorbing molecules

A rifle fires a 2.10 x 10^-2 kg pellet straight upward, because the pellet rests on a compressed spring when the trigger is is pulled. the spring has negligible mass and it is compressed by 9.10 x 10^-2 m from is unstrained length.

How much force is needed to stop an 80kg football player if he decelerates at 5m/s2

If a spacecraft that seems to be motionless in deep space is given some type of quick push, what will happen? A. The spacecraft will not move because it only works on earth. B.

A fast, white water cascade is also known as what?

What is a stack of membranes that packages chemicals

Under what condition (s) will an object be in equilibrium? Notice that equilibrium in physics has a broader definition. (A) Only if it is moving with constant velocity. (B) Only if it is at rest.

If a pressure gauge measure an increase in 3*10^ (5) Pa on an area of 0.7 m^2, calculate the increase in the force applied to the area?