JEE Main Test 1...

What is the period of revolution of the earth satellite? Ignore the height of satellite above the surface of the earth. Given, (1) The value of gravitational acceleration, g = 10 m/s ². (2) Radius of the earth, R_E = 6400 km (take, π = 3.14)

Charges + 2q, + q and +q are placed at the corners A ,B and C of an equilateral triangle ABC. If E is the electric field at the circumcentre O of the triangle, due to the charge +q, then the magnitude and direction of the resultant electric field at O is

A stationary point source of sound emits sound uniformly in all directions in a non-absorbing medium. Two points P and Q are at a distance of 4 m and 9 m respectively from the source.

The ratio of amplitudes of the waves at P and Q is

The charge on the capacitor of capacitance C shown in the figure below will be

In the given circuit, a charge of + 80 µC is given to the upper plate of the 4 µF capacitor. Then, in the steady state, the charge on the upper plate of the 3 µF capacitor is

If the bisector of the angle P of a triangle PQR meets QR in S, then

If in a ∆ ABC, a = 15, b = 36, c = 39, then sin C/2 is equal to