Instantaneous Speed

Understanding Rest And Motion|Frame Of Reference|Introduction To Mechanics|Kinematics|Motion In A Straight Line|Practice Exercise|Position Vector And Displacement Vector|Distance And Displacement|Average Speed And Average Velocity|Instantaneous Velocity And Instantaneous Speed|Average And Instantaneous Acceleration|Practice Exercise|Summary

Which of the following statements is /are correct ? I.Average speed over a finite interval of times is greater or equal to the magnitude of the average velocity. The instantaneous speed at an instant is equal to the magnitude of the instantaneous velocity at that instant.

A small ball (mass m) falling under gravity in a viscous medium experience a drag force proportional to the instantaneous speed u such that F_(drag)=ku . Then the terminal speed of ball within viscous medium is

A disc is rolling on a rough horizontal surface. The instantaneous speed of the point of contact during perfect rolling is zero with respect to ground. The force of friction can help in achieving pure rolling condition.

A ball is moving in a circular path of radius 5m. If tangential acceleration at any instant is 10 m//s^(2) and the net acceleration makes an angle 30^(@) with the centripetal acceleration, then the instantaneous speed is

A particle of mass 100 g, is made to describe a vertical circle of radius 1 m. Its instantaneous speed is 1ms^(-1) when the string makes an sngle of 30^(@) with the vertical Find the tension in the string at this position. Can the particle complete its circular path? (g=10ms^(-2))

Read each statement below carefully and state with reasons, if it is true ot false. (a) During rolling the force of friction acts in the same direction as the direction of motion of c.m of the body. (b) The instantaneous speed of the point of contact during rolling is zero. (c ) The instantaneous acceleration of the point of contact during rolling is zero. (d) For perfect rolling motion, work done against friction is zero. (e) A wheel moving down a perfectly frictionless inclined plane will undergo slipping (not rolling motion).

A car moving at 160 km//h when passes the mark-A, driver applies brake and reduces its speed uniformly to 40 km//h at mark-C. The mark are spaced at equal distances along the road as shown below. At which part of the track the car has instantaneous speed of 100 km//h ? Neglect the size of the car.