In a two-dimensional motion, instantaneous speed is a positive constant. Then which of the following is necessarily true?
1. | the average velocity is not zero at any time. |
2. | average acceleration must always vanish. |
3. | displacements in equal time intervals are equal. |
4. | equal path lengths are traversed in equal intervals. |
In a two-dimensional motion, instantaneous speed is a positive constant. Then which of the following is necessarily true?
1. | The acceleration of the particle is zero. |
2. | The acceleration of the particle is increasing. |
3. | The acceleration of the particle is necessarily in the plane of motion. |
4. | The particle must be undergoing a uniform circular motion. |
The following are four different relations about displacement, velocity and acceleration for the motion of a particle in general.
(a) | \(v_{a v}=1 / 2\left[v\left(t_1\right)+v\left(t_2\right)\right]\) |
(b) | \(v_{\mathrm{av}}=\mathrm{r}\left(\mathrm{t}_2\right)-\mathrm{r}\left(\mathrm{t}_1\right) / \mathrm{t}_2-\mathrm{t}_1\) |
(c) | \(r=1 / 2\left[v\left(t_2\right)-v\left(t_1\right)\right]\left(\mathrm{t}_2-\mathrm{t}_1\right)\) |
(d) | \(\mathrm{a}_{\mathrm{av}}=v\left(\mathrm{t}_2\right)-v\left(\mathrm{t}_1\right) / \mathrm{t}_2-\mathrm{t}_1\) |
The incorrect alternative/s is/are:
1. | (a, d) |
2. | (a, c) |
3. | (b, c) |
4. | (a, b) |