Position \(x\) of a particle moving on a straight line as a function of time \(t\) is \(x =(2t^{2}-12t+5) \text{ m}.\) The particle will come to rest at time \(t\) equal to:
1. \(2\) s
2. \(1\) s
3. \(4\) s
4. \(3\) s
The position of an object moving along the \(x\text-\)axis is described by:
\(x=(a+bt^2 ),\)
where \(a=10\text{ m},\) \(b=2\text{ m/s}^2,\) and \(t\) is measured in seconds. What is the velocity of the object at \(t=3.0\text{ s}\text{?}\)
| 1. | \(12\text{ m/s}\) | 2. | \(20\text{ m/s}\) |
| 3. | \(36\text{ m/s}\) | 4. | \(46\text{ m/s}\) |
| 1. | \(A\) | 2. | \(B\) |
| 3. | \(C\) | 4. | \(D\) |
The coordinates of a moving particle at any time \(t\) are given by; \(x=\alpha t^3,\) and \(y=\beta t^3.\) The speed of the particle at time \(t\) is given by:
1. \(\sqrt{(\alpha^2+\beta^2)}\)
2. \(3t \sqrt{(\alpha^2+\beta^2)}\)
3. \(3t^2 \sqrt{(\alpha^2+\beta^2)}\)
4. \(t^2 \sqrt{(\alpha^2+\beta^2)}\)
Two cars \(P\) and \(Q\) start from a point at the same time in a straight line and their positions are represented by; \(x_p(t)= at+bt^2\) and \(x_Q(t) = ft-t^2. \) At what time do the cars have the same velocity?
| 1. | \(\dfrac{a-f}{1+b}\) | 2. | \(\dfrac{a+f}{2(b-1)}\) |
| 3. | \(\dfrac{a+f}{2(b+1)}\) | 4. | \(\dfrac{f-a}{2(1+b)}\) |