Question

I need help with the folowing (4) questions!

1. How much force is used if 60J of work were necessary to lift an object 3m?

A.180N

B.0.05N

C.20N

D.200N

2. How much power is used to push a car with a force of 870N a distance of 65m in 500 seconds?

3. Calculate the efficiency of a machine with a work output of 3100j and a work input of 4600j.

A.1.48%

B.148%

C.6.73%

D.67.39%

4. Why is the actual mechanical advantage of a machine always less than its ideal mechanical advantage?

A.The presence of friction results in the actual mechanical advantage of a machine always being more than its ideal mechanical advantage.

B.The presence of friction results in the actual mechanical advantage of a machine always being less than its ideal mechanical advantage.

Answer 1

Answer:

1. force × displacement = workdone

force = work/displacement=60/3=20