Home » Posts tagged 'sec'

# Tag Archives: sec

## Velocity and acceleration of a Ferrari !

A **Ferrari** covers120m from a standing start in 6sec at constant acceleration.Find its final velocity

(Shilvastar asked this)

**Answer**:

u=0 (Since it starts from rest)

t= 6s

s=120m

a=?

v=?

from

a=2 x 120/36=6.67 m/s^{2}

from v=u+at

v=40m/s

## Kinematics Numerical

- A particle travels 20 m in 7th second and 24m in 9th sec. find initial velocity?
- in a projectile motion , a body thrown from the ground ,at what angle both the vertical height and range will be equal?
- The velocity v(cm/s) of a particle is given in terms of time t(in seconds) by the equation v = at+b/t+c. Dimension of a,b, and c are ?

## More problems coming in; Try to answer now!

Stuti posted these:

- a particle is thrown with any velocity vertically upward. the distance traveled by particle in last sec of ascent is 1)g 2)g/2 3)g/4 4)cant be calculated
- a ball is dropped from a bridge of 122.5 metre above a river. after ball has been falling for 2 sec,a second ball is thrown straight down after it. initial velocity of second ball so that both hit water at sme time is 1)49 m/s 2)55.5 m/s 3)26.1 m/s 4)9.8 m/s.
- two cars are moving in same direction with a speed of 30 km/hr. they are separated from each other by 5 km. third car moving in opposite direction meets the two cars after an interval of 4 minutes. the speed of third car is 1)30 km/hr 2)25 km/hr 3) 40 km/hr 4)45 km/hr
- a balloon starts rising from ground from rest with an upward acceleration 2 m/s^2. jst after 1 sec , a stone is dropped from it. time taken by stone to strike ground is nearly 1)0.3 sec 2)0.7 sec 3)1 sec 4)1.4 sec