A body of mass 2 kg is kept by pressing to a vertical wall by a force of 100 N . The friction is 0.04 , what is the car's aceeleration ?

1 answer

To determine the acceleration of the body being pressed against the wall, we can assess the forces acting on it.

  1. Given Data:

    • Mass of the body \( m = 2 , \text{kg} \)
    • Applied force \( F_{applied} = 100 , \text{N} \)
    • Coefficient of friction \( \mu = 0.04 \)
    • Gravitational acceleration \( g \approx 9.81 , \text{m/s}^2 \)
  2. Calculate the normal force \( F_N \): The normal force is equal to the applied force, as the body is pressed against the wall: \[ F_N = F_{applied} = 100 , \text{N} \]

  3. Calculate the frictional force \( F_f \): The maximum static friction can be calculated using the coefficient of friction and the normal force: \[ F_f = \mu \times F_N = 0.04 \times 100 , \text{N} = 4 , \text{N} \]

  4. Assess the forces acting on the body:

    • The gravitational force acting downward: \[ F_{gravity} = m \times g = 2 , \text{kg} \times 9.81 , \text{m/s}^2 \approx 19.62 , \text{N} \]

    • The frictional force acting upward (opposing the gravitational force): \[ F_f = 4 , \text{N} \]

  5. Calculate the net force acting on the body: The net force acting on the body can be calculated as the difference between the gravitational force and the frictional force: \[ F_{net} = F_{gravity} - F_f = 19.62 , \text{N} - 4 , \text{N} = 15.62 , \text{N} \]

  6. Calculate the acceleration \( a \) of the body: By applying Newton's second law \( F = m \times a \), we can find the acceleration: \[ a = \frac{F_{net}}{m} = \frac{15.62 , \text{N}}{2 , \text{kg}} \approx 7.81 , \text{m/s}^2 \]

Therefore, the car's acceleration is approximately \( 7.81 , \text{m/s}^2 \).