A body is executing uniform circular motion in a circle of radius 100 m at speed 10 m/s. Acceleration of the body is :
(1) Zero
(2) 2
(3) 1
(4) 5
An object of mass m is projected from the ground with a momentum \(p\) at such an angle that its maximum height is \(\frac{1}{4}\)th of its horizontal range. Its minimum kinetic energy in its path will be:
1. | \(\frac{p^2}{8 m} \) | 2. | \(\frac{p^2}{4 m} \) |
3. | \(\frac{3 p^2}{4 m} \) | 4. | \(\frac{p^2}{m}\) |
Which of the following is the angle between velocity and acceleration of a body in uniform circular motion?
1. \(30^\circ\)
2. \(45^\circ\)
3. \(60^\circ\)
4. \(90^\circ\)
A person is rotating in a horizontal circle of radius 7 m. Find the period of rotation for which the acceleration is equal to 3g.
(1) 2.6 s
(2) 2.8 s
(3) 3.1 s
(4) 4.3 s
A ball is projected horizontally from the top of wall A of height 80 m with speed 10 m/s. At what distance from the wall ball hits the ground?
(1) 20 m
(2) 50 m
(3) 60 m
(4) 40 m
An aeroplane flies \(400\) m north and then \(300\) m west and then flies \(1200\) m upwards. Its net displacement is:
1. | \(1200\) m | 2. | \(1300\) m |
3. | \(1400\) m | 4. | \(1500\) m |
Which of the following is an appropriate expression for the radius of curvature of a projectile at the highest point? (R Range of projectile)
(1)
(2)
(3) 2R cot
(4) 2R tan
A park is in the shape of a regular hexagon. Six friends standing at each corner of the park start moving towards each other with the same speed 2 m/s and meet each other after 60 s. The side of the park is
(1) 120 m
(2) 30 m
(3) 240 m
(4) 60 m
A ball is projected horizontally from a cliff 40 m high at a speed of 40 m/s and simultaneously a ball is dropped. If the time taken by the two balls to reach the ground are respectively (taking air friction into consideration), then
(1)
(2)
(3)
(4) Depending on air friction maybe less or more than
Select the incorrect statement:
1. | It is possible to have \(\left|\frac{{d} \overrightarrow{v}}{dt}\right| = 0 \) and \(\frac{{d}|\overrightarrow{v}|}{{dt}} \neq 0 \) |
2. | It is possible to have\(\left|\frac{{d} \overrightarrow{{v}}}{{dt}}\right| \neq 0 \) and \(\frac{{d}|\overrightarrow{{v}}|}{dt}=0 .\) |
3. | it is possible to have\(\left|\frac{{d} \overrightarrow{v}}{{dt}}\right|=0\) and \(\frac{{d}|\overrightarrow{{v}}|}{dt}=0 . \) |
4. | It is possible to have \(\left|\frac{{d} \overrightarrow{{v}}}{{dt}}\right| \neq 0\) and \(\frac{{d} \overrightarrow{{v}}}{{dt}} \neq 0 \) |