List of top Physics Questions

If the radius of earth is reduced by 1% without changing the mass, then change in the acceleration due to gravity will be:
At atmospheric pressure, the water boils at $ 100{}^\circ C $ . If pressure is reduced, it will boil at :
A body projected vertically upwards with a velocity u returns to the starting point in $4 s$. If $g = 10 \,m s^{-2}$, the value of $u$ in $m/s$ is
Fertile material among the following is
A circular loop of radius R, carrying current I, lies in x-y plane with its centre at origin. The total magnetic flux through x-y plane is
The critical angle for glass-water boundary is C. If $ {{\mu }_{g}}=1.5 $ 1.5 and $ {{\mu }_{\omega }}=\frac{4}{3} $ then the value of C is:
When the wavelength of light coming from a distant star is measured it is found shifted towards red. Then the conclusion is:
Hot water kept in a beaker placed in a room cools from $ 70{}^\circ C $ to $ 60{}^\circ C $ in 4 minutes. The time taken by it to cool from $ 69{}^\circ C $ to $ ~59{}^\circ C $ will be:
When light of wavelength $ \lambda $ falls on a thin film of thick- ness t and refractive index n, the essential conditions for the production of constructive interference fringes by the rays A and B is: (m = 1,2,3,...)
A force acts on a 3 g particle in such a way that the position of the particle as a function of time is given by x = 3t - 4t$^2$ + t$^3$, where x is in metres and t is in seconds. The work done during the first 4 second is
11. A real image of a distant object is formed by a planoconvex lens on its principal axis. Spherical aberration
The width of river is 1 km. The velocity of boat is 5 km/hr. The boat covered the width of river in shortest time 15 min. Then the velocity of river stream is
A voltmeter has a range 0-V with a series resistance R. With a series resistance 2 R, the range is 0-V'. The correct relation between V and V' is
The speed of radio-waves is equal to:
A car moving with a speed of 40 km/h can be stopped by applying brakes after at least 2 m. If the same car is moving with a speed of 80 km/h, what is the minimum stopping distance?
Newton?? formula for the velocity of sound in gases, is
An aeroplane is flying horizontally with a velocity of 216 km/h and at a height of 1960 m. When it is vertically above a point A on the ground, a bomb is released from it. The bomb strikes the ground at point B. The distance AB is (ignoring air resistance)
The rate of difusion is
Which of the following pairs does not have same dimension?
A copper ball is heated to $ 100{}^\circ C $ . It cools to $ 80{}^\circ C $ in 5 minutes and to $ 65{}^\circ C $ in 10 minutes. The temperature of the surrounding is
A lift is ascending with an acceleration equal to g/3 What will be the time period of a simple pendulum suspended from its ceiling if its time period in stationary lift isT:
A galvanometer of 100 $ \Omega $ resistance gives full scale deflection with 0.01 A current. How much resistance should be connected to convert it into an ammeter of range , 10 A :
A spherical surface of radius of curvature R, separates air (refractive index 1.0) from glass (refractive index 1.5). The centre of curvature is in the glass. A point object P placed in air is found to have a real image Q in the glass. The line PQ cuts the surface at a point O and PO = O The distance PO is equal to
A ball of mass 0.25 kg attached to the ends of a string of length 1.96 m is rotating in a horizontal circle. The string will break, if tension is more than 25 N. What is the maximum velocity with which the ball can be rotated?
A coil of one turn is made of a wire of certain length and then from the same length a coil of two turns is made. If the same current is passed in both the cases, then the ratio of the magnetic inductions at their centres will be