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A particle moving along x-axis has acceleration f, at time t, given by f = f0(1 - (t/T)) , where f0 and T are constants. The particle at t = 0 has zero velocity. In the time interval between t = 0 and the instant when f = 0, the particle’s velocity (vx) is
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- 1/2 f0T²
- f0T²
- 1/2 f0T
- f0T.
Correct Option: C
Here, ƒ = ƒ0 | ![]() | 1 - | ![]() | or, | = ƒ0 | ![]() | 1 - | ![]() | |||
T | dt | T |
or, dv = ƒ0 | ![]() | 1 - | ![]() | dt | |
T |
∴ v = ∫ dv = ∫ | ![]() | ƒ0 | ![]() | 1 - | ![]() | ![]() | dt | |
T |
or v = ƒ0 | ![]() | t - | ![]() | + C | |
2T |
where C is the constant of integration.
At t = 0, v = 0.
∴ 0 = ƒ0 | ![]() | 0 - | ![]() | + C ⇒ C = 0 | |
2T |
∴ v = ƒ0 | ![]() | t - | ![]() | ||
2T |
if ƒ = 0, then
0 = ƒ0 | ![]() | t - | ![]() | ⇒ t = T | |
2T |
Hence, particle's velocity in the time interval t = 0 and t = T is given by
vx = t = T∫t = 0 dv = T∫t = 0 | ![]() | ƒ0 | ![]() | 1 - | ![]() | ![]() | dt | |
T |
= ƒ0 | ![]() | ![]() | t - | ![]() | ![]() | T | ||
2T | 0 |
= ƒ0 | ![]() | T - | ![]() | = ƒ0 | ![]() | T - | ![]() | = | ƒ0T | |||
2T | 2 | 2 |