Question

A horizontal force of magnitude 30.0 N pushes a block of mass 4.20 kg a distance of 3.00 m across a floor where the coefficient of kinetic friction is 0.600.

What is the acceleration of the block?

a. 1.80 m/s²
b. 2.00 m/s²
c. 2.20 m/s²
d. 2.40 m/s²

Answer 1

The acceleration of the block is approximately d) 2.40 m/s².

Step-by-step explanation:

To find the acceleration of the block, we can use Newton's second law of motion, which states that the net force acting on an object is equal to the mass of the object multiplied by its acceleration. In this case, the net force is the horizontal force minus the frictional force. The horizontal force is 30.0 N, and the frictional force can be calculated using the coefficient of friction (0.600) and the normal force (equal to the weight of the block, which is m*g). Therefore, the frictional force is 0.600 * m * g. Plugging in the given values, we have:

Net force = 30.0 N - 0.600 * 4.20 kg * 9.8 m/s²

Next, we can use the formula for acceleration:

Acceleration = Net force / mass

Substituting the values, we get:

Acceleration = (30.0 N - 0.600 * 4.20 kg * 9.8 m/s²) / 4.20 kg

Calculating this gives us an acceleration of approximately 2.40 m/s².