Question 4.1:
Newton's second law of motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. Mathematically, this can be expressed as F = ma, where F is the net force acting on the object, m is the mass of the object, and a is the acceleration of the object.
Question 4.2:
Free-body diagram for block A:
- Tension force (T) acting to the right
- Normal force (N) acting upwards
- Weight force (W) acting downwards
- Frictional force (f) acting to the left
Question 4.3:
To calculate the acceleration of the blocks, we need to consider the net force acting on block A. The only horizontal force acting on block A is the frictional force (f), which is equal to the coefficient of friction (μ) times the normal force (N). The normal force (N) is equal to the weight of block A, which is equal to its mass (3.3 kg) times gravity. So, N = 3.3 kg * 9.8 m/s^2.
The frictional force (f) is equal to μ * N, where μ = 0.1.
The tension force (T) in the string is equal to the weight of block B, which is equal to its mass (2.1 kg) times gravity. So, T = 2.1 kg * 9.8 m/s^2.
The net force acting on block A is given by the difference between the tension force (T) and the frictional force (f), so:
Net force = T - f
Acceleration can be calculated using Newton's second law: F = ma. So, the acceleration is a = (T - f) / m, where m = 3.3 kg.
Substitute the values to calculate the acceleration.
Two blocks, A and B, of the masses 3,3kg and 2,1kg respectively, are joined by an inextensible string. The string is threaded through a frictionless pulley allowing block B to be suspended by it. The coefficient between block A and the surface of the table is 0,1.
Figure 6: Diagram showing two blocks connected by a string.
Question 4.1 [2 marks]
Define Newton’s second law of motion.
Question 4.2 [4 marks]
Draw a labelled free-body diagram showing all the forces acting on block A. Question 4.3 [5 marks]
Calculate the acceleration of the blocks.
1 answer