Question

a car of mass 800 kilogram is travelling with a velocity of 20 metre per second.when brakes are applied it stops after travelling a distance of 8 metre find retardation and retarding force.

pls answer correctly if wrong I will report the answer ​

Answer 1

Explanation:

s=8

m=800

u=20

v=0

v^2-u^2=2as

-400=2×a×8

-400÷16=a

a=-25

retardation is -25 and is aways negative

Answer 2

Answer:

retardation (a) = -25 m/s^2

retarding force (F) = -20,000 N

Explanation:

Given - mass (m) = 800 kg

            initial velocity (u) = 20 m/s

            distance  (x) = 8 m

            final velocity (v) = 0 m/s

i) To find retardation -

   v^2 = u^2 + 2ax

    (0)^2 = (20)^2 + 2(a)(8)

    0 = 400 + 16a

    -400 = 16a

    a = -400/16

    a = -25 m/s^2

ii) To find retarding force -

     F = ma

     F = 800 x (-25)

     F = -20,000 N