What is the net force needed to lift a full grocery sack (weighing 210 N) uniformly? What is the net force needed to accelerate the grocery sack upward at 1.5 m/s 2 ?
To lift the grocery sack uniformly (at a constant velocity) you would need to apply a force equal to the weight of the sack, which is 210 N. This is because the net force required to lift an object at an unchanging velocity is equal to its weight to counteract the force of gravity.
To accelerate the grocery sack upward at 1.5 m/s^2, you would need to apply a net force greater than its weight. The net force required can be calculated using the equation F = ma, where F is the net force, m is the mass of the object (which can be calculated by dividing the weight by the acceleration due to gravity, 9.81 m/s^2) and a is the acceleration.
First, calculate the mass of the grocery sack:
m = 210 N / 9.81 m/s^2
m = 21.41 kg
Now, plug the values into the formula:
F = 21.41 kg * 1.5 m/s^2
F = 32.115 N
Therefore, the net force needed to accelerate the grocery sack upward at 1.5 m/s^2 is 32.115 N.