A small block of mass 100 g is pressed against a horizontal spring fixed at one end to compress the spring through 5.0 cm. The spring constant is 100 N/m. When released, the block moves horizontally till it leaves the spring. Where will it hit the ground 2 m below the spring?

Answer

A, C, D

Explanation

`m=100 g=0.1 kg`
`=5cm=0.05m`
`k=100N/m`
When the body leaves the spring let the velocity be v.
`1/2mv^2=1/2kx^2`
`rarr v=xsqrt(k/m)`
`=(0.05)xxsqrt((100)/(0.1))`
` =1.58 m/sec for the projectile moton
`theta=0^0,y=-2`
Now, `y=(u.sintheta)t-1/2gt^2`
`-2=(-1/2)xx(9.8)xxt^2`
`rarr t=0.63 sec`
`So, x=(ucostheta)t` ltbr. `=(1.58)xx(0.63)=1m`