A mechanical device requires 420 J of work to do 230 J of work to lift a crate. What is the efficiency of the device? 190% 0.5% 183% 55%

A material that causes a wave to bounce off of it

What are the advantages of division of labor and the disadvantages of division of labor

How much work would you have to do in order to lift a 60 n object 2.5 meters?

Which of the following is a sign that a person may be attempting to meet an unrealistic health goal? weight loss muscle strength tendon rupture joint flexibility

a horizontal force of 100N is required to push a crate across a factory floor at a constant speed. What is the net force acting on the crate / What is the force of friction acting on the crate?

Two workers pull horizontally on a heavy box but one pulls twice as hard as the other. The larger pull is directed at 25.0 west of north and the resultant of these pulls is 430.0N directly northward.

What would happen to an object in orbit without gravity pulling down?

The waters of a lake will be most layered in which season A. winter B. spring C. summer D. fall

Which of the following is an example of an archery contestant showing good precision but poor accuracy? O A. Hitting a bulls-eye once and then missing a second time O B. Hitting a bulls-eye every time O C.

List and describe two ways currents affect life on earth