CBSE
Multiple Choice QuestionsA projectile is given an initial velocity of î + 2 ĵ . The cartesian equation of its path is ( Take g = 10 ms2 )
y = x - 5x2
y = 2x - 5x2
y = 2x - 15x2
y = 2x - 25x2
Two projectiles of same mass have their maximum kinetic energies in ratio 4:1 and ratio of their maximum height is also 4:1 then what is the ratio of their ranges?
2 : 1
4 : 1
8 : 1
16 : 1
A stone projected with a velocity u at an angle θ with the horizontal reaches maximum height H1. When it is projected with velocity u at an angle with the horizontal, it reaches maximum height H2. The relation between the horizontal range R of the projectile, H1 and H2 is
R =
R = 4 ( H1 - H2 )
R = 4( H1 + H2 )
R =
In figure, a particle having mass m = 5 g and large q'= 2 x 10-9 starts from rest at point and moves in a straight line to point b. What is its speed v at point b?
2.65 cms-1
3.65 cms-1
4.65 cms-1
5.65 cms-1
If are non-zero vectors which obey the relation , then the angle between them is
0o
60o
90o
120o
Assertion: Two balls of different masses are thrown vertically upward with same speed. They will pass through their point of projection in the downward direction with the same speed.
Reason: The maximum height and downward velocity attained at the point of projection are independent of the mass of the ball.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion is true but reason is false.
A particle slides down on a smooth incline of inclination 30°, fixed in an elevator going up with an acceleration 2 m/s2. The box of incline has a length 4m. The time taken by the particle to reach the bottom will be
( 8/9 ) √3 s
( 9/8 ) √3 s
( 4/3 ) √(√3/2 ) s
( 3/4 ) √(√3/2 ) s
A particle moves in a circular path with decreasing speed. Choose the correct statement.
Angular momentum remains constant
Acceleration is towards the centre
Particle moves in a spiral path with decreasing radius
The direction of angular momentum remains constant
An arrow is projected into air. Its time of flight is 5 s and range 200 m. What is the maximum height reached by it? ( Take g= 10 ms-2 )
31·25 m
24·5 m
18·25 m
46·75 m
A particle is projected from the ground with an initial speed of 'v' at angle θ with horizontal. The average velocity of the particle between its point of projection and height point of trajectory is
vcosθ
