Question

Block A has a mass of 2 kg and block B has 20 kg. If the coefficient of kinetic friction between block B and the horizontal surface is 0.1, and B is accelerating towards the right with a = 2 m/s², then the mass of the block C will be ______.

(g = 10 m/s²)

 

पर्याय

• 15 kg

• 12.5 kg

• 5.7 kg

• 10.5 kg

Answer 1

Block A has a mass of 2 kg and block B has 20 kg. If the coefficient of kinetic friction between block B and the horizontal surface is 0.1, and B is accelerating towards the right with a = 2 m/s², then the mass of the block C will be 10.5 kg.

Explanation:

For A block

T – m_Ag = m_Aa

T – 20 = 2a

T = 24 N

For block B

T’ – T – f = m_Ba

T’ – 24 – 20 = 20 × 2

T’ = 40 + 44

T’ = 84 N

`{{:("since"  "f" = mu"m"_"B""g"), (= 0.1 xx 20 xx 10), (= 20  "N"):}}`

For block C

m_cg – T’ = m_ca

m_cg = 84 + 2 m_c

8 m_c = 84;

m_c = 10.5 kg