For the first part, we are looking for Vf when dy=11.0
Upward is positive, downward is negative.
So <span>Vf = square root [2(-9.8)(11.0) + (18.0)^2] </span>
<span>Vf = 10.4 m/s your answer is correct.
For the part b, t is equals to the time took to reach and dy is equals to 11.0
you did, </span>11= 18t m/s-(1/2) 9.8t^2 then <span>-11 + 18t- 9.8t^2. By quadratic formula, for the way down the answer is 2.9 s while on it's way up, the answer is 0.77 s</span><span>
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When two bodies collide with each other in the absence of an external force, then the total final momentum of the bodies is equal to their total initial momentum.
Answer:
0.833
Explanation:
Power = energy / time
Power = force × distance / time
Power = force × velocity
P = (850 kg) (9.8 m/s²) (1.00 m/s)
P = 8330 W
P = 8.33 kW
The efficiency of the motor is therefore:
e = 8.33 kW / 10.0 kW
e = 0.833
Answer:
The approximate change in entropy is -14.72 J/K.
Explanation:
Given that,
Temperature = 22°C
Internal energy 
Final temperature = 16°C
We need to calculate the approximate change in entropy
Using formula of the entropy

Where,
= internal energy
T = average temperature
Put the value in to the formula


Hence, The approximate change in entropy is -14.72 J/K.