Class XI Physics Kinematics 5

If a vector  making angles α, β, and γ respectively with the X, Y and Z axes respectively.

Then sin² α + sin² β + sin² γ =

If the resultant of n forces of different magnitudes acting at a point is zero, then the minimum value of n is

A vector  is turned without a change in its length through a small angle dθ. The value of  and Δa are respectively

Find the resultant of three vectors  and  shown in the following figure. Radius of the circle is R.

A force  (where K is a positive constant) acts on a particle moving in the x-y plane. Starting from the origin, the particle is taken along the positive x- axis to the point (a, 0) and then parallel to the y-axis to the point (a, a). The total work done by the forces  on the particle is

A projectile moving vertically upwards with a velocity of 200 ms^-1 breaks into two equal parts at a height of 490 m. One part starts moving vertically upwards with a velocity of 400 m/s. How much time it will take, after the break up with the other part to hit the ground?

The maximum range of a bullet fired from a toy pistol mounted on a car at rest is  What will be the acute angle of inclination of the pistol for maximum range when the car is moving in the direction of firing with uniform velocity  on a horizontal surface?

A ball projected from ground at an angle of 45^o just clears a wall in front. If point of projection is 4m from the foot of wall and ball strikes the ground at a distance of 6m on the other side of the wall the height of the wall (in m) is :