575 - Physics Questions Answers

Physics >> Mechanics Part 2 >> Gravitation Medical Exam

Two point masses having mass m and 2m are placed at distance d. The point on the line joining point masses, where gravitational field intensity is zero will be at distance

Asked By: SWATI KAPOOR
is this question helpfull: 3 1 submit your answer
Joshi sir comment

let the point will be at a distance of x from m then compare the gravitational field of the two masses at that point

Physics >> Mechanics Part 2 >> Gravitation Medical Exam

If earth suddenly stop rotating, then the weight of an object of mass m at equator will [ ω is angular speed of earth and radius R is its radius]

Asked By: SWATI KAPOOR
is this question helpfull: 3 1 submit your answer
Joshi sir comment

In rotating condition mass at equator is mg-mRω2

if earth stops rotation then it will become mg so increases by mRω2

Physics >> Mechanics Part 2 >> Gravitation Medical Exam

Three particles A,B and C each of mass m are lying at the corners of an equilateral triangle of side L. If the particle A is released keeping the particles B and C fixed, the magnitude of instantaneous acceleration of A is

Asked By: SWATI KAPOOR
is this question helpfull: 5 0 submit your answer
Joshi sir comment

force by the other two on A = Gmm/L2 each but the angle between the two forces is 60 degree so resultant force = √3Gmm/L2

now calculate acceleration?

A large number of identical point masses m are placed along x-axis, at x= 0,1,2,4.........The magnitude of gravitational force on mass at origin (x=0), will be

Asked By: SWATI KAPOOR
is this question helpfull: 4 2 submit your answer
Joshi sir comment

The magnitude of gravitational force on mass at origin (x=0), will be

Gmm/12 + Gmm/22 + Gmm/42 + Gmm/8+ .........................

= [Gmm/12][1+(1/4)+(1/16)+....................]

= Gmm[1/(1-(1/4)]

solve?

Physics >> Mechanics Part 2 >> Gravitation Medical Exam

A satellite of mass 200 kg revolves around a planet of mass 5 x 1030kg in a circular orbit of radius 6.6 x 106 m. Binding energy of the satellite.

Asked By: SWATI KAPOOR
is this question helpfull: 1 1 read solutions ( 1 ) | submit your answer
Joshi sir comment

Binding energy = GMm/2R

What is the minimum coefficient of friction for a solid sphere to roll without slipping on an inclined plane of inclination θ?

Asked By: SWATI KAPOOR
is this question helpfull: 5 1 submit your answer
Joshi sir comment

friction f = mgsinθ/[1+(mr2/I)]

solve for sphere and compare to μmgcosθ

 

A particle moving with constant acceleration covers a distance of 30m in the 3rd second. it covers a distance of 50m in the 5th  second. What is the acceleration of the particle?

Asked By: GAUTAM SAGAR
is this question helpfull: 2 1 submit your answer
Joshi sir comment

use formula for the distance covered in a particular second 

st = u+at-(a/2)

A particle is moving with a velocity of 10m/s due east. In One second its velocity changes to 10m/s due west. If the particle is uniformly accelerated, the change in velocity will be directed as

Asked By: GAUTAM SAGAR
is this question helpfull: 1 0 submit your answer
Joshi sir comment

let east is i

then velocity change = -10i-10i = -20i

A  ball is dropped from a height h reaches the ground in time T. What is its height at time T/2

Asked By: GAUTAM SAGAR
is this question helpfull: 3 0 submit your answer
Joshi sir comment

h = 1/2 gT2

in T/2 time h' = 1/2 gT2/4 = 1/8 gT2

so height from ground = h-h'

solve?

Asked By: GAUTAM SAGAR
is this question helpfull: 3 1 submit your answer
Joshi sir comment

see you tube video of iitbrain by the name I E Irodov problem 1.3

Login Here

Register