Which of the following is a compound machine?

Bicycle

Pulley

Ramp

Wedge

Which of the following is used to calculate mechanical advantage?

Fr/Fe

dr/de

de/dr

Fe/Fr

A man weighing 700 N lifts 50.0 N object 2.0 m high. He uses a lever and with a force of 10.0 N. What is the resistance force?

120 N
10.0 N
700 N
50.0 N

A pilgrim uses a block and tackle to lift a 225 N crate a distance of 16.5 m. She pulls 33.0 m of rope with a force of 129 N. What is the ideal mechanical advantage of machine?

0.50
2.00
1.74
0.573

Distance covered, s = 8ft - 4ft = 4 ftinitial velocity, u = 34 ft/sthe acrobat is moving upwards and therefore, a = -g = -9.81 m/s^2 = 32.19 ft/s^2applying equation of motion; s = ut -1/2gt^2then,4 = 34t -1/2*32.19t^24 = 34t - 16.095t^2rearranging; -16.095t^2 + 34t - 4 = 0solving the quadratic equation; t = {-34 +/- sqrt [34^2 - 4(-16.)]}/2(-16.095) = 1.06 +/- 0.93 = 0.13 or 1.99the acrobat will take 0.13 seconds to be at 8 ft above the ground. additionally, once at the maximum height, the acrobat will move down and be at the same spot (that is height) after 1.99 seconds moving down.

The answer would be d. hope this : ))

A=v^2/r solve for r hope that