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%

If an electrically uncharged body is contacted by an electrically charged body, the uncharged body will A. develop the opposite charge as the charged body. B. remain a neutrally charged body. C. neutralize the charged body. D.

A 5.5 kg bowling ball initially at rest is dropped from the top of a 12 m building. It hits the ground 1.75 s later. Find the net external force on the falling ball.

After hearing about an accident on his normal route Mr. Gujral checks for alternate routes to get to work what type of circuit does this traffic situation model

How are work and power related?

A model used for the yield y of an agricultural crop as a function of the nitrogen level n in the soil (measured in appropriate units) is y = kn 1 + n2 where k is a positive constant. what nitrogen level gives the best yield?

Contrast balanced and unbalanced forces.

A wave will travel only as long as it has energy

a box sliding on a frictionless surface when it suddenly begins to rain heavily. if the downpour of rainfall falls vertically into the box, gradually filling it, what would happen to the speed of the box

Which would fall with a greater acceleration in a vacuum-a leaf or a stone?

A force acts on a 5kg object at rest. How fast will the object accelerate on a frictionless surface? A.) 4 m/s^2 B.) 15 m/s^2 C.) 25 m/s^2 D.) 100 m/s^2