Answer:
1890J
Explanation:
375+45 = 420kg (total mass)
kinetic energy = 1/2 × mass × velocity²
1/2 × 420 × 3² = 1890J
Change in speed = (speed at the end) minus (speed at the beginning)
= (0 - 20 m/s) = -20 m/s
Acceleration = (change in speed) / (time for the change)
= (-20 m/s) / (3.5 sec) = -5.71 m/s²
Notice that this story probably didn't happen on Earth, because
the acceleration due to gravity on Earth is 9.8 m/s².
Answer: 6611.715 joules
Explanation:
Q = MxCxdeltaT = 6959.7 which is 100%
95% = 6611.715
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