A block of mass 4kg is placed in contact with the front vertical surface of a lorry. The coefficient of friction between the vertical surface and block is 0.8.The lorry is moving with an acceleration of 15 m/ s² .The force of friction between lorry and block is (g =10 ms^-2)

• A

  48N

• B

  24N

• C

  40N

• D

  Zero