A particle starts from the origin at t=0 and moves in the x-y plane with constant acceleration 'a' in the y direction. Its equation of motion is . The x component of its velocity (at t=0) is:
(1) variable
(2)
(3)
(4)
The \(x\) and \(y\) coordinates of the particle at any time are \(x = 5t-2t^2\) and \(y=10t\) respectively, where \(x\) and \(y\) are in metres and \(t\) is in seconds. The acceleration of the particle at \(t=2\) s is:
1. \(0\)
2. \(5\) m/s2
3. \(-4\) m/s2
4. \(-8\) m/s2
A particle moves so that its position vector is given by \(r=\cos \omega t \hat{x}+\sin \omega t \hat{y}\) where \(\omega\) is a constant. Based on the information given, which of the following is true?
1. | Velocity and acceleration, both are parallel to r. |
2. | Velocity is perpendicular to r and acceleration is directed towards the origin. |
3. | Velocity is not perpendicular to r and acceleration is directed away from the origin. |
4. | Velocity and acceleration, both are perpendicular to r. |
A body is moving with velocity 30 m/s towards east. After 10 s its velocity becomes 40 m/s towards north. The average acceleration of the body is
(1)
(2)
(3)
(4)
A particle moves in space such that:
\(x=2t^3+3t+4;~y=t^2+4t-1;~z=2sin\pi t\)
where \(x,~y,~z\) are measured in meters and \(t\) in seconds. The acceleration of the particle at \(t=3\) seconds will be:
1. | \(36 \hat{\mathrm{i}}+2 \hat{\mathrm{j}}+\hat{\mathrm{k}} \) ms-2 |
2. | \(36 \hat{\mathrm{i}}+2 \hat{\mathrm{j}}+\pi \hat{\mathrm{k}} \) ms-2 |
3. | \(36 \hat{\mathrm{i}}+2 \hat{\mathrm{j}} \) ms-2 |
4. | \(12 \hat{\mathrm{i}}+2 \hat{\mathrm{j}} \) ms-2 |
A particle moves along a parabolic path y = 9x2 in such a way that the x component of the velocity remains constant and has a value of . It can be deduced that the acceleration of the particle will be:
1.
2.
3.
4.
If the position of a particle varies according to the equations x = 3, y = 2t, and z = 4t + 4, then which of the following is incorrect?
1. | Velocities in y and z directions are constant |
2. | Acceleration in the x-direction is non-uniform |
3. | Acceleration in the x-direction is uniform |
4. | Motion is not in a straight line |
The position vector of a particle as a function of time t (in seconds) is . The initial acceleration of the particle is:
1. 2
2. 3
3. 4
4. Zero
At an instant, the velocity and acceleration of a particle moving in the XY plane are m/s and . Rate of change of speed of the particle at this instant is:
(1)
(2) -1
(3) 1
(4) Zero
A particle is moving along a curve. Select the correct statement.
1. | If its speed is constant, then it has no acceleration. |
2. | If its speed is increasing, then the acceleration of the particle is along its direction of motion. |
3. | If its speed is decreasing, then the acceleration of the particle is opposite to its direction of motion. |
4. | If its speed is constant, its acceleration is perpendicular to its velocity. |