Physics Questions and Answers
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
4.0 m
5.0 m
2.0 m
1.5 m
Correct answer is C
For a simple pendulum, the period T = 2π
√ 1/g
Since g, 2 and π are constant, => T ∝ √l
∴ T = K√l
Let the original length = l
thus for the length l, period T = 17s
∴ 17 = K√1 .................. [1]
Again, for the new length [1 - 1.5]
the period T = 8.5s
∴ 8.5 = k
√ [1-1.5] ...............[2]
thus dividing eqn [1] by eqn[2] we have
17/8.5 = √(l/l-1.5)
∴2 = √(l/l-1.5)
=>4 = (l/l-1.5)
∴l = 4[l-1.5]
= 4l - 6.0
∴4l - l = 6.0
3l = 6.0
l = 2.0m
60 ms-2
20 ms-2
15 ms-2
10 ms-2
Correct answer is B
The velocity V = 10 + 2t2
But acceleration, a = dv/dt
thus if V = 10 + 2t2
dv/dt = 4t
And t = 5s then a = 4x5 = 20m/s2
∴a = 20ms
2V
10V
14V
48V
Correct answer is E
The effective V =
√ VR2 + VL2
=
√ 62 + 82
=
√ 36 + 64
=
√ 100
10V
R2/R1
R1/R2
R1+R2/R1
R1+R2/R2
Correct answer is A
Power = IV = I2R = V2/R
In terms of e.m.f E, of a cell we have
IE = I2R = E2/R
∴P1 = E2/R; P2 = E2/R2/E2/R2
= E2/R1 x R2/E2 = R2/R1
∴P1/P2 = R2/R1
