CBSE
Two particles which are initially at rest, move towards each other under the action of their internal attraction. If their speeds are v and 2v at any instant, then the speed of centre of mass of the system will be
2v
0
1.5 v
1.5 v
A missile is fired at maximum range with an initial velocity of 20 m/s. If g =10 m/s2 the range of the missile is
50 m
60 m
20 m
20 m
A projectile is fired an angle of 45o with the horizontal.Elevation angle of the projectile at the highest point as seen from the point of projection is
60o
tan-1(1/2)
A Particle has initial velocity and has acceleration.
Its speed after 10s is
7 unit
8.5 unit
8.5 unit
A particle moves a distance x in time t according to equation x = (t +5)-1. The acceleration of particle is proportional to
(velocity)3/2
(distance)2
(distance)-2
(distance)-2
A body is moving with velocity 30 m/s towards east. After 10 s its velocity becomes 40 m/s towards the north. The average acceleration of the body is
7 m/s2
5 m/s2
5 m/s2
Two particles A and B, move with constant velocities v1 and v2. At the initial moment, their position vectors are r1 and r2 respectively. The condition for particles A and B for their collision is
r1.v1 = r2.v2
r1 x v1 = r2 x v2
r1 x v1 = r2 x v2
The velocity of a projectile at the initial point A is (2 i + 3 j) m/s. Its velocity (in m/s) at point B is,
-2 i - 3 j
-2 i + 3 j
2 i - 3 j
2 i - 3 j
Six vectors and
have the magnitudes and directions indicated in the figure. Which of the following statements is true?
A particle of mass m is released from rest and follows a parabolic path is shown. Assuming that the displacement of the mass from the origin is small, which graph correctly depicts the position of the particle as a function of time?