Answer:
Explanation:
Intake heat, QH = 100 J
output heat, Qc = 20 J
Work, W = 80 J
TH = 100°C = 373 K
Tc = 10°C = 283 K
TH/ Tc = 373 / 283 = 1.318
QH/Qc = 100 / 20 = 5
for a heat engine, those ratios should be same. so temperature is not correct.
Picking up a sheet of paper . . . work done with small force
Picking up a glass of water . . . work done with moderate force
Picking up a huge boulder . . . work done with a great tremendous force
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Standing still . . .
Holding your tongue out as far as it will go . . .
Holding your arm over your head for 3 days . . .
Holding a huge boulder motionless over your head . . .
Pushing on a brick wall . . .
Pushing as hard as you can against a truck with the wheels locked . . .
. . . . . No work done at all, because the force doesn't move through a distance.
<u>Work done = (force) times (distance)</u>
If the force doesn't move, then the distance is zero, and the work done is zero.
Answer:
Counterclockwise
explanation in attachment
Answer: The correct choice is, B: protons
Explanation:
Protons have a positive charge whereas neutrons have no charge and electrons have a negative charge. Due to positive charge of protons, nucleus of an atom acquires a positive charge. Therefore, we can conclude that protons are the particles give the nucleus its positive charge.
Answer:
Explanation:
Loss of potential energy = mgh.
h = d sin 20
= 400 sin20 = 136.8 m
Loss of potential energy = m x 9.8 x 136.8
= 1340.64 m
negative work done by friction = μ mg cosθ x d
= .2 x m x 9.8 x cos 20 x 400
= 736.72 m
Net loss of potential energy = 1340.64 m - 736.72 m
= 603.92 m
= gain of kinetic energy = 1/2 m v²
1/2 m v² = 603.92 m
v² = 1207.84
v = 34.75 m /s .
