A fireman directs a stream of water into the watertight bed of a truck. The wate

Question

A fireman directs a stream of water into the watertight bed of a truck. The water emerges horizontally from the nozzle at rate 244.0 kg/min with speed 36.10 m/s. Take the water to hit the front of the bed of the truck horizontally and then to drop down and accumulate without splashing out. The mass of the truck (bed empty) is 2000 kg and it is free to move without friction. (a) Initially the truck is at rest and the bed is empty. What is the magnitude of its acceleration at that instant? (b) Two minutes later the truck is moving with a speed of 7.08 m/s. What is its acceleration at that instant?

Explanation / Answer

F t = mv
F = mv/ t = (m/t) * v

But also F = Ma
so a = F/ M = (m/t) * v / M
= 244 * 36.10 / 2000 m/s^2 =4.40 m/s^2

b)

initially at rest = 0

now . velocity = 7.08 m/s

time t = 2 mins = 120 sec

we know that v =u+at

7.08 = 0+a*120

a = 0.059 m/s^2

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.