A 920 kg block is pushed on the slope of a 30

frictionless inclined plane to give it an initial

speed of 50 cm/s along the slope when the block is 2.3 m from the bottom of the incline.

The acceleration of gravity is 9.8 m/s2. What is the speed of the block at the bot-

tom of the plane?

Answer in units of m/s

Question

Physics

Bryan Burke

16 November, 04:38

A 920 kg block is pushed on the slope of a 30

frictionless inclined plane to give it an initial

speed of 50 cm/s along the slope when the block is 2.3 m from the bottom of the incline.

The acceleration of gravity is 9.8 m/s2. What is the speed of the block at the bot-

tom of the plane?

Answer in units of m/s

+1

Answers (1)

Know the Answer?

Teresa Garcia · Answer 1

Using the kinetic energy theorem, we have:

sumW = 1/2 mV²final - 1/2mV²initial

sumW=mgh, where h=sin30 x AB, AB = 2.3m

50 cm/s=0.5m/s

so 2g sin30 AB = V²final - V²initial and V final = sqrt (2gsin30 AB + V²initial)

finally v = 4.77m/s