Question

1 ) a 100 long truck crosses 200m bridge with a velocity of 36km/h find the time token by the truck to cross the bridge
ans=205 using formula s=d/t
2) acceleration = ( v- u)m/s×2/t
where v=final velocity
u=initial velocity
t=time
use this formula to solve this problem
3) a car traveling at a velocity of 10m/s due to north sphere up unformily to a velocity of 25m/s in 3 s calculate the acceleration during this period
ans=5m/s using a=v.v/t​

Answer 1

Given:

The length of long truck is  100 m

The bridge length is 200 m

The speed of the truck is 36 km/hr

To find:

The time taken, acceleration in both the cases.

Solution:

For the First question:

The total distance covered is 100+200= 300 m

The speed of the truck is  36 Km/hr= 10 m/sec

So the time taken is t=d/s

Putting the above value we get.

t=300/10

t=30 sec

For the second question:

v=u+at

(v-u)/t=a

Putting the above values

(36-0)/30=a

a=1.2 m/sec²

For the third question:

The u= 10 m/sec

v=25 m/sec

t= 3 sec

The equation of motion is

(v-u)/t=a

(25-10)/3=a

a=5 m/sec²

So the time taken is 30 sec, the acceleration in both cases are 1.2 and 5 m/sec²