You are in an elevator that is accelerating upwards at 2m/s^2. If your mass is 70kg, what is the normal force pushing on you by the floor of the elevator?
A. 70N
B. 690N
C. 830N
Please give the correct answer and an explanation as to why its correct.
with zero acceleration, F=mg due to gravity.
Now add F=ma due to the upward acceleration.
The correct answer is C. 830N.
To determine the normal force pushing on you, we need to consider the forces acting on your body while in the elevator. In this case, there are two forces: the gravitational force pulling you downwards and the normal force pushing you upwards.
The gravitational force acting on your body can be calculated using the formula F = m * g, where m is the mass of your body and g is the acceleration due to gravity (approximately 9.8 m/s^2).
F_gravity = 70kg * 9.8m/s^2 = 686N
Now, since the elevator is accelerating upwards at 2 m/s^2, there is an additional force exerted on your body in the upward direction. This force can be calculated using the formula F = m * a, where m is the mass of your body and a is the acceleration of the elevator.
F_upward = 70kg * 2m/s^2 = 140N
Since the normal force is the force that pushes you upwards, the total normal force can be calculated by adding the gravitational force and the upward force:
Total normal force = F_gravity + F_upward = 686N + 140N = 826N
Therefore, the correct answer is C. 830N.