Mechanics | Relativity Answers

A student repeatedly measured the length of a simple pendulum and recorded the results in centimetre as: 36.9, 36.7, 36.8 and 36.6. What is the precision index of this measurement in cm?

when the air is pumped out if a lidded can, air remains only on the upper side of the lid. A spring balance is then used to determine the amount of lifting force required to raise the lid. Suppose we observe that for a can with a diameter of 12.0 cm and a lid weight of 2.0 N, the lid does not come off until the spring balance reading exceeds 1144 N. Find the air pressure on the upper lid of the can.

a heavy solid sphere is thrown on a horizontal rough surface with initial velocity 7 m/s without rolling.when it starts pure rolling motion,then its speed will be??

the linear mass density of a rod of length 1 meter is P=(4+X),then the position of centre of mass from X=0 end of the rod is?

a disc of mass M and R radius is rolling purely wid centre of velocity v on a flat surface,then it hits a step in the floor of height R/4.
the corner of step is sufficiently rough to prevent any slipping of disc against itself.what is the velocity of centre of disc just after the impact?

Why passengers planes fyl at low altitudes?

the motion of a car along y-axis is given by v(t)=-12t+12 where velocity v is in m/s and time t in seconds. find the instantaneous position of the car as a function of time if at t=0 it was at 5m. Also find its acceleration at t =2 second.

find the expression for the energy density in terms of stress andstrain

Suppose a trolley of mass 5Kg is carrying a mass of 35 kg is pushed by a boy so that it start moving with 4m/s. It travelled 16m and stopped.
A)What is the work done on the trolley?
B)What is the work done by the trolley?

Calculate the amount of heat conducted in 45 min through an iron plate 5-cm thick and with an area of 2 sq m. The two sides are kept at 0°C and 60°C. (Kfc=0.12)