A driver takes 0.30 s to apply the brakes after he sees a need for it. This is called the reaction time of the driver. If he is driving a car at a speed of 54 km/h and the brakes cause a deceleration of 5.0m/s2, find the distance travelled by the car after he sees the need to put the brakes on ?

Anonymous User Physics 15 Apr, 2019 1 Answer 86 views



The force of repulsion between two point charges is F, when these are at a distance of 1 m. Now the point charges are replaced by spheres of radii 25 cm having the charge same as that of point charges. The distance between their centres is 1 m, then compare the force of repulsion in two cases.

Anonymous User Physics 13 Apr, 2019 1 Answer 1356 views









A particle is moving along a straight line along x-axis with an initial velocity of 2 m/s towards positive x-axis. A constant acceleration of 0.5 m/s2 towards negative x-axis starts acting on particle at t=0. Find velocity (in m/s) of particle at t = 2s.

Rahul Kumar Physics 12 Apr, 2019 1 Answer 74 views

A body is thrown up with a speed 49 m/s. It travels 5 m in the last second of its upward journey. If the same body is thrown up with a velocity 98 m/s, how much distance (in m) will it travel in the last second. (g = 10 m/s2)?

Rahul Kumar Physics 12 Apr, 2019 1 Answer 208 views


















A solid sphere of mass M and radius R is surrounded by a spherical shell of same mass M and radius 2R as shown. A small particle of mass m is released from rest from a height h (<<R) above the shell. There is a hole in the shell.

Devendra Yadav Physics 12 Apr, 2019 0 Answer 91 views

If the law of gravitation be such that the force of attraction between two particles vary inversely as the 5/2th power of their separation, then the graph of orbital velocity v0 plotted against the distance r of a satellite from the earth's centre on a log-log scale is shown alongside. The slope of line will be

Ashish Yadav Physics 12 Apr, 2019 1 Answer 154 views









An open glass tube is immersed in mercury in such a way that a length of 8 cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46 cm. What will be length of the air column above mercury in the tube now?

Anonymous User Physics 10 Apr, 2019 1 Answer 133 views


Rita performs two set of experiments to study the length of the foam formed which are as follows:
Set I: she takes 10 ml of distilled water in test tube “A” and adds 5-6 drops of liquid soap in it and shakes the test tube vigorously.
Set II: she takes 10 ml of distilled water in a test tube “A” and adds 5-6 drops of liquid soap with half spoonful of CaSO 4 in it and shakes the test tube. Write your observation and reason

Anonymous User Biology 10 Apr, 2019 2 Answer 71 views





A box of mass m is initially at rest on a horizontal surface. A constant horizontal force of mg/2 is applied to the box directed to the right. The coefficient of friction of the surface changes with the distance pushed as µ = µ0x where x is the distance from the initial location. For what distance is the box pushed until it comes to rest again?

Anonymous User Physics 09 Apr, 2019 1 Answer 153 views