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4 years ago

If the total momentum of a system is changing:

Physics

1 answer:

DENIUS [597]4 years ago

3 0

Answer:

(d) a net external force must be acting on the system

Explanation:

Momentum is given as the product of mass and velocity.

P = MV

According to Newton's second law of motion, " Force applied to a body (system) is directly proportional to the rate of change of momentum of the body (system) which takes place in the direction of the applied force (external force).

F ∝ΔMV

Therefore, If the total momentum of a system is changing, a net external force must be acting on the system.

(d) a net external force must be acting on the system

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3 years ago

The resistanceless inductor is connected across the ac source whose voltage amplitude is 24.5 V and angular frequency is 850 rad

timurjin [86]

Answer:

Part A 2.88 A, PART B 28.82 mA PART C 0.288 mA

Explanation:

We have given angular frequency $\omega =850rad/sec$

Voltage source has an amplitude of 24.5 V, So V= 24.5 volt

Part A

We have given inductance $L=10^{-2}H$

So inductive reactance $X_L=\omega L=850\times 10^{-2}=8.5ohm$

So current $i=\frac{V}{X_L}=\frac{24.5}{8.5}=2.8823A$

Part B

We have given inductance $L=1 H$

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So current $i=\frac{V}{X_L}=\frac{24.5}{850}=28.82mA$

Part C

We have given inductance $L=100 H$

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3 years ago

A ball whose mass is 0.3 kg hits the floor with a speed of 5 m/s and rebounds upward with a speed of 2 m/s. If the ball was in c

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Answer:

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Explanation:

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Equating this to impulse formula then

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$F=\frac {m(v-u)}{t}$

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3 years ago

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3 years ago

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Answer:

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3 years ago