Rain is falling vertically downward with a speed of \(35~\text{m/s}\). Wind starts blowing after some time with a speed of \(12~\text{m/s}\) in East to West direction. The direction in which a boy standing at the place should hold his umbrella is:
1. | \(\text{tan}^{-1}\Big(\dfrac{12}{37}\Big)\) with respect to rain |
2. | \(\text{tan}^{-1}\Big(\dfrac{12}{37}\Big)\) with respect to wind |
3. | \(\text{tan}^{-1}\Big(\dfrac{12}{35}\Big)\) with respect to rain |
4. | \(\text{tan}^{-1}\Big(\dfrac{12}{35}\Big)\) with respect to wind |
1. | \(3000~\text{m}\) | 2. | \(2800~\text{m}\) |
3. | \(2000~\text{m}\) | 4. | \(1000~\text{m}\) |
1. | \(4\sqrt2~\text{ms}^{-1},45^\circ\) | 2. | \(4\sqrt2~\text{ms}^{-1},60^\circ\) |
3. | \(3\sqrt2~\text{ms}^{-1},30^\circ\) | 4. | \(3\sqrt2~\text{ms}^{-1},45^\circ\) |
1. | \(\overrightarrow v\) is a constant; \(\overrightarrow a\) is not a constant. |
2. | \(\overrightarrow v\) is not a constant; \(\overrightarrow a\) is not a constant. |
3. | \(\overrightarrow v\) is a constant; \(\overrightarrow a\) is a constant. |
4. | \(\overrightarrow v\) is not a constant; \(\overrightarrow a\) is a constant. |
1. | \( \theta=\sin ^{-1}\left(\dfrac{\pi^2 {R}}{{gT}^2}\right)^{1/2}\) | 2. | \(\theta=\sin ^{-1}\left(\dfrac{2 {gT}^2}{\pi^2 {R}}\right)^{1 / 2}\) |
3. | \(\theta=\cos ^{-1}\left(\dfrac{{gT}^2}{\pi^2 {R}}\right)^{1 / 2}\) | 4. | \(\theta=\cos ^{-1}\left(\dfrac{\pi^2 {R}}{{gT}^2}\right)^{1 / 2}\) |
A car starts from rest and accelerates at \(5~\text{m/s}^{2}\). At \(t=4~\text{s}\), a ball is dropped out of a window by a person sitting in the car. What is the velocity and acceleration of the ball at \(t=6~\text{s}\)? (Take \(g=10~\text{m/s}^2)\)
1. \(20\sqrt{2}~\text{m/s}, 0~\text{m/s}^2\)
2. \(20\sqrt{2}~\text{m/s}, 10~\text{m/s}^2\)
3. \(20~\text{m/s}, 5~\text{m/s}^2\)
4. \(20~\text{m/s}, 0~\text{m/s}^2\)
1. | constant acceleration. |
2. | constant velocity but varying acceleration. |
3. | varying velocity and varying acceleration. |
4. | constant velocity. |