Answer:
Explanation:
Power P = V² / R
a ) The resistance is changed to 2.90R
Power will become 1 / 2.9 times .
b )The voltage of the battery is now 2.90V, but the resistance is R
P = (2.9V)² / R
= 8.41 x V² / R
So power becomes 8.41 times
c )The resistance is 2.90R and voltage is 2.90V
Power P = (2.9V)² / 2.9 R
= 2.9 V²/R
So power becomes 2.9 times
d ) The resistance is 2.90R and the voltage is V/2.90
Power P = ( V/2.90)² x 1 / 2.90R
1 / ( 2.9 )³ x V² / R
= 1 / 24.389 x V² / R
So power becomes 1 / 24.389 times .
Answer:
Uniform rectilinear movement (m. r. u.)
Explanation:
It is a continuous movement without acceleration, that is, it moves at a constant speed. The speed does not change over time, for this reason, there is no change in acceleration.
Vf = final velocity = 50/30 [km/s] = 1.67 [km/s]
Vo = initial velocity = 50/30 [km/s] = 1.67 [km/s]
Answer:
B) 20N.s is the correct answer
Explanation:
The formula for the impulse is given as:
Impulse = change in momentum
Impulse = mass × change in speed
Impulse = m × ΔV
Given:
initial speed = 40m/s
Final speed = -60 m/s (Since the the ball will now move in the opposite direction after hitting the bat, the speed is negative)
mass = 0.20 kg
Thus, we have
Impulse = 0.20 × (40m/s - (-60)m/s)
Impulse = 0.20 × 100 = 20 kg-m/s or 20 N.s
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