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3 years ago

13

The motor of a four wheeler traveling along a muddy trail generates an average power of 7.48 104 W when moving at a constant spe

ed of 13 m/s. When pulling a log along the trail at the same speed, the engine must generate an average power of 8.50 104 W. What is the tension in the tow rope pulling the log?

2 answers:

Radda [10]3 years ago

7 0

Answer:

The tension in the tow rope pulling the log is 784.61 N

Explanation:

Given:

v = speed = 13 m/s

Pf = final power when the log is pulled = 8.5x10⁴W

Pi = average power = 7.48x10⁴W

The force required to move a car is equal to:

$F_{i} =\frac{P_{i} }{v} =\frac{7.48x10^{4} }{13} =5753.85 N$

$F_{f} =\frac{P_{f} }{v} =\frac{8.5x10^{4} }{13} =6538.46 N$

T = Ff - Fi = 6538.46 - 5753.85 = 784.61 N

DiKsa [7]3 years ago

7 0

Answer: 784.6 N

Explanation:

Given

Power of the motor, P1 = 7.48*10^4 W

Speed of the motor, v = 13 m/s

Power of the motor, P2 = 8.5*10^4 W

It is known that

Power = J/t, where

J = work, in joules

t = time, in seconds. Also,

Work = F * d, where

F = force

d = distance, thus on substituting, we have,

Power = Fd/t

Also, we know that

Velocity = d/t, where

d = distance,

t = time, thus, we could say that

Power = Force * Velocity

P = FV

To find the tension in the log, we use

F = P/V, where

P = P2 - P1

P = 8.5*10^4 - 7.48*10^4

P = 1.02*10^4 = 10200W

Force, F = 10200 / 13

F = 784.6 N

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