A motor car is going due north at a speed of 50 km/h. It makes a 90° left turn without changing the speed. The change in the velocity of the car is about.
1. 50 km/h towards west
2. 70 km/h towards south-west
3. 70 km/h towards north-west
4. zero
A particle has a velocity \(u\) towards east at \(t=0\). Its acceleration is towards west and is constant. Let \(x_A\) and \(x_B\) be the magnitude of displacements in the first \(10\) seconds and the next \(10\) seconds respectively. Then:
1. | \(x_A < x_B\) |
2. | \(x_A = x_B\) |
3. | \(x_A > x_B\) |
4. | \(x_A\) with \(x_B\) | the information is insufficient to decide the relation of
In a projectile motion the velocity,
1. | is always perpendicular to the acceleration |
2. | is never perpendicular to the acceleration |
3. | is perpendicular to the acceleration for one instant only |
4. | is perpendicular to the acceleration for two instants |
Two bullets are fired simultaneously, horizontally and with different speeds from the same place. Which bullet will hit the ground first?
1. | the faster one |
2. | the slower one |
3. | both will reach simultaneously |
4. | depends on the masses |
The range of a projectile fired at an angle of \(15^\circ\) is \(50\) m. If it is fired with the same speed at an angle of \(45^\circ,\) its range will be:
1. \(25\) m
2. \(37\) m
3. \(50\) m
4. \(100\) m
Two projectiles A and B are projected with angle of projection 15° for the projectile A and 45° for the projectile B. If RA and RB be the horizontal range for the two projectiles, then
1. RA < RB
2. RA = RB
3. RA > RB
4. the information is insufficient to decide the relation of RA with RB
A river is flowing from west to east at a speed of 5 metres per minute. A man on the south bank of the river, capable of swimming at 10 metres per minute in still water, wants to swim across the river in the shortest time. He should swim in a direction:
1. | due north |
2. | \(30^\circ\) east of north |
3. | \(30^\circ\) north of west |
4. | \(90^\circ\) east of north |
Consider the motion of the tip of the minute hand of a clock. In one hour:
a. | the displacement is zero |
b. | the distance covered is zero |
c. | the average speed is zero |
d. | the average velocity is zero |
Choose the correct option:
1. (a) and (b)
2. (b) and (c)
3. (c) and (d)
4. (a) and (d)