Answer:
(a) 
(b) 
Explanation:
Let:
mass of father be, 
mass of son be, 
speed of son be, 
initial speed of father be, 
After speeding up, speed of father is 
<u>We know Kinetic Energy is given as</u>
.....................................(1)
where:
m = mass
v = velocity
Hence, according to the initial condition the father is having kinetic energy half the kinetic energy of the son.



.................................................(2)
According to the final condition:



.....................................................(3)
(a)
From eq. 2 & 3





(b)
<em>putting the above value in eq. (2)</em>

We have equation of motion v = u + at
Where v = final velocity, u = initial velocity, a = acceleration, and t = time
In this case car is travelling in -x direction
Velocity of car = displacement / time
Since displacement value is increasing in negative x axis it's initial velocity is negative
And it's final velocity is zero since it comes to rest, and time is also positive
So, v= u+ at => 0 = -u + at
So, a = u/t
Which is positive and along positive X - direction
Yes I can help jus tell me what the 26th question is
Yes because once the accident has happen the air bag will then push out