Which of the following statement is correct in connection with projectiles?

A path, traced by a projectile in the space, is known as trajectory.
The velocity with which a projectile is projected, is known as the velocity of projection.
The angle, with the horizontal, at which a projectile is projected is known as angle of projection.
all of the above
✅ The correct answer is option D.

A block ot mass 20 kg lying on a rough horizontal plane is connected by a light string passing over a smooth pulley to another mass 5 kg, which can move freely in the Vertical direction, as shown in the below figure. The tension in the string will __________ with the increase in coefficient of friction.

increase
decrease
not be effected
✅ The correct answer is option A.