Saranya jogs from one end A to the other end B of a straight road of length 320m in 2 min 40 seconds. Then she turns back and jogs 100m to point C in 1 min. what is her average velocity in jogging.

A car is moving along a straight line (OP). It moves from O→P in 18 seconds amd retuns from P→Q in 6 seconds, where OP = 360 m and OQ = 240 m. What is the average velocity and average speed of the car going (a) from O→P and back to Q ?

Point masses m_1 and m_2 are placed at the opposite ends of a rigid rod of length L, and negligible mass . The position of point p on this rod through which the axis should p on this rod through which the axis should pass so that the work required to set the rod rotating with angular velocity omega_0 is minimum , is given by: .

A steel tube of length 1.00 m is struck at one end. A person with his ear close to the other end hears the sound of the blow twice one travelling through the body of the tube and the other through the air in the tube. Find the time gap between the two hearings.

Figure shows a small block of mass m kept at the left end of a larger block of mass M and length l. The system canslide on a horizontal road. The system is started towards right with an initia velocity v. The friction coefficient between the road and the bigger block is mu and that between the block is mu/2 . Find the time elapsed before the smaller blocks separates from the bigger block.

A string of linear mass density 0.5 g cm^-1 and a total length 30 cm is tied to a fixed wall at one end and to a frictionless ring at the other end. The ring can move on a vertical rod. A wave pulse is produced on the string which moves towards the ring at a speed of 20 cm s^-1 . The pulse is symmetric about its maximum which is located at a distance of 20 cm from the end joined to the ring. (a) Assuming that the wave is reflected from the ends without loss of energy, find the time taken by the string to regain its shape. (b) The shape of the string changes periodically with time. Find this time period. (c) What is the tension in the string ?

Figure shows an aluminium rod joined to a copper rod. Each of the rods has a length of 20cm and area of cross section 0.20cm^(2) . The junction is maintained at a constant temperature 40^(@)C and the two ends are maintained at 80^(@)C . Calculate the amount of heat taken out from the cold junction in one minute after the steady state is reached. The conductivities are K_(Al)=200Wm^(-1)C^(-1) . and K_(Cu)=400Wm^(-1)C^(-1) .