Basic Science T...

The mass of a lift is 2000 kg. When the tension in the supporting cable is 28000 N, then its acceleration is

The refractive index of glass is measured and values are $$1.49,1.50,1.52,1.54$$ and $$1.48$$. Percentage error in the measurement is

A particle $$m$$ starts with zero velocity along a line $$y=4d$$. the 
position of particles $$m$$ varies as $$x=A \sin \omega t$$ At $$\omega 
t=\pi/2$$ its angular momentum with respect to the origin

The ratio of accelerations $$a_{1}$$ and $$a_{2}$$ of block of mass m as shown in figure (i) and (ii) are

A body is dropped from a height of $$100\ m$$. At what height the velocity of the body will be equal to half of velocity when it hits the ground.

A perfectly elastic ball is thrown against a wall and bounces back over the head of the thrower $$(T),$$ as shown in the figure:
when it leaves the thrower's hand, the ball is $$2\,m$$ above the ground, $$4\,m$$ away from the wall and has initial velocity of $$10\sqrt{2}\,m/s$$ at an angle of $$45^\circ$$ to horizontal. The ball will hit the ground at an approximate horizontal distance of

A rocket with a lift-off mass $$3.5 \times 10^{4}\,kg$$ is blasted upwards with an initial acceleration of $$10\,ms^{-2}.$$ Then the initial thrust of the blast is

A particle is dropped from a height of $$20\ m$$. Speed with which the particle will hit the ground is

Initial velocity of a particle moving along straight line with constant acceleration is $$(20 \pm 2) \ m/s$$, if its acceleration is $$a=(5 \pm 0.1) \ m/s^2$$, then velocity of particle with error, after time $$t=(10 \pm 1) \ s$$, is

Two point masses $$m$$ and $$3m$$ are placed at distance $$r$$, The moment of inertia of the system about an axis passing through the centre of mass of system and perpendicular to the line joining the point masses is