- #1

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the problem is

a moving car t velocity of 20 ms(-1) brakes to a standstill in a distance of 40m, a child of mass 15kg is sitting in a forward facing child car seat fitted to the back-seat of the car

calculate (1) the deceleration (2) the force on the child

i always thought to calculate the deceleration is braking distance/ mass but the only mass given is that of the child and surely the car will way more than that, hence why i dont understand what formula to use, is it using suvat? if so i cant find a suvat formula with only s U and v, its driving me mad ( no pun intended)

for the second part of the question I haven't been told any information on how to work it out but is the formula t= 2s/U + v (t is time, s is distance/displacement, U is initial velocity and v is final velocity