Final answer:
The consistent force of friction (Fr) acting on a 4 kg block sliding at a constant velocity of 1.5 m/s on a table is 4.9 N. This is because the hanging 0.5 kg mass exerts a force of 4.9 N, which is opposed by the frictional force keeping the block moving at constant velocity.
Step-by-step explanation:
To determine the consistent force of friction (Fr) acting between the block and the table while the block is sliding at constant velocity, we can use the fact that the net force on the block in the horizontal direction must be zero (since it is moving with constant velocity). The force due to the hanging mass (m) is causing the block to slide, and this force can be calculated as the weight of the hanging mass, which is m × g (where g is the acceleration due to gravity). Assuming g is 9.8 m/s², the force due to the hanging mass is 0.5 kg × 9.8 m/s² = 4.9 N. This force is being opposed by the force of friction (Fr), and since the block is moving at a constant velocity, Fr must equal 4.9 N.