Question

a block of mass 0.5 kg rests ona horizontal surface when a horizontal of force 2.0 newton on it it acquires an acceleration of 3m/sec square the force of friction btween the block and the horizontal surface is

Answer 1

Given :

Mass of the block = 0.5kg

Applied force = 2N

Acceleration = 3m/s²

To Find :

Force of friction between the block and the horizontal surface.

Solution :

❖ As per newton's second law of motion, force is measured as the product of mass and acceleration.

• Force is a polar vector quantity as it has a point of application.
• SI unit : N

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In this case, force of friction acts in the opposite direction hence it opposes the motion of block.

Net force on the block will be (F - f)

• F denotes applied force
• f denotes frictional force

➙ (F - f) = m × a

➙ 2 - f = 0.5 × 2

➙ 2 - f = 1

➙ f = 2 - 1

➙ f = 1 N

Answer 2

Given :

Mass of the block = 0.5kg

Applied force = 2N

Acceleration = 3m/s²

To Find :

Force of friction between the block and the horizontal surface.

Solution :

❖ As per newton's second law of motion, force is measured as the product of mass and acceleration.

Force is a polar vector quantity as it has a point of application.

SI unit : N

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In this case, force of friction acts in the opposite direction hence it opposes the motion of block.

Net force on the block will be (F - f)

F denotes applied force

f denotes frictional force

➙ (F - f) = m × a

➙ 2 - f = 0.5 × 2

➙ 2 - f = 1

➙ f = 2 - 1

➙ f = 1 N