A bomb is dropped from an aeroplane flying horizontally. The path of the bomb as seen by the pilot will be (neglect air friction)
(1) A straight line
(2) A parabola
(3) An ellipse
(4) A hyperbola
The range of a bullet fired from a gun at an angle with the horizontal is the same as the range of another bullet fired from that gun at an angle with the horizontal. Then,
1.
2.
3.
4.
A boy runs on a circular track of radius \(R\) (in km) with a speed of \(\dfrac{πR}{2}\) km/h in the clockwise direction for \(3\) h and then with \(πR\) km/h in the anticlockwise direction for \(1\) h. The magnitude of his displacement will be:
1. \(\dfrac{πR}{2}\)
2. \(\dfrac{R}{\sqrt{2}}\)
3. \(\dfrac{3πR}{2}\)
4. \(\sqrt{2}R\)
Two projectiles P and Q are projected with the same speed at angles 60° and 30° with horizontal on level ground, then: [R = Range, T = Time of flight, H = Maximum height]
(1)
(2)
(3)
(4) All of these
A body is projected with the same speed at two different angles covers the same horizontal distance R. If are two times of flights, then R is equal to :
1.
2.
3.
4.
A body starts moving from rest on a horizontal ground such that the position vector of the body with respect to its starting point is given by \(r= 2 t\hat{i}+3t^2\hat j\). The equation of the trajectory of the body is:
1. \(y =1.5x\)
2. \(y =0.75x^2\)
3. \(y =1.5x^2\)
4. \(y =0.45x^2\)
A particle starts moving with constant acceleration with initial velocity (\(\hat{\mathrm{i}}+5\hat{\mathrm{j}}\)) m/s. After \(4\) seconds, its velocity becomes (\(3\hat{\mathrm{i}}-2\hat{\mathrm{j}}\)) m/s. The magnitude of its displacement in 4 seconds is:
1. \(5\) m
2. \(10\) m
3. \(15\) m
4. \(20\) m
A particle is revolving in a circular path of radius 200 m at a speed of 20 m/s. Its speed is increasing at a rate of . Its acceleration is :
(1) 2
(2)
(3) 3
(4)
The ratio of maximum height attained by two projectiles of the same mass is 25: 9. The ratio of their minimum kinetic energy is 4: 9. The ratio of their ranges is:
(1) 25: 4
(2) 10: 9
(3) 5: 2
(4) 1: 1
If a particle is moving in a circular orbit with constant speed, then:
1. | its velocity is variable. |
2. | its acceleration is variable. |
3. | its angular momentum is constant. |
4. | All of the above |