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Olin [163]
3 years ago
8

What is the change in internal energy if 20 J of heat is released from a system and the system does 50 J of work on the surround

ings?
a. -70 j
b. 30 j
c. -30 j
d. 70 j
Physics
2 answers:
viva [34]3 years ago
8 0

OPTION - A

Change in energy given by :-

dQ = du + dw

dQ = -20 - (-50)

dQ = -70

siniylev [52]3 years ago
7 0
Answer is A.

Both energy changes describe energy be lost from the system (in different forms - as heat or as work). The negative sign indicates loss.
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A golfer tees off and hits a golf ball at a speed of 31 m/s and at an angle of 35 degrees. How long was the ball in the air? Rou
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Answer:

3.6 seconds

Explanation:

Given:

y₀ = y = 0 m

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3 years ago
A car is traveling 35 mph on a smooth surface. If a balanced force is applied to the car, what happens?
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Here is the answer.

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7 0
3 years ago
A wheel of radius 30 cm is rotating at a rate of 2.0 revolutions every 0.080 s. (A) through what angle, in radians, does the whe
ioda

You said 2 revolutions every 0.08 seconds

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7 0
3 years ago
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