Jay (65 kg) is standing on a scale in an elevator holding an apple. The elevator begins to accelerate downwards at 2.4 m/s2.
What does the scale read during this acceleration?
would it be 793 N or 481N?
N=m(g-a) OR
N=m(g+a)? and why plz!
Nevermind i got the answer it would be - because the elevator accelerates downward
To determine what the scale reads when Jay is standing on it in the accelerating elevator, we need to consider the forces acting upon him. The two main forces to consider are his weight (due to gravity) and the force exerted on him by the elevator floor (normal force).
The equation N = m(g - a) represents the forces acting on Jay if we consider the positive direction to be upwards. Here:
- N is the normal force exerted by the scale,
- m is the mass of Jay (65 kg),
- g is the acceleration due to gravity (approximately 9.8 m/s²), and
- a is the acceleration of the elevator (2.4 m/s²).
In this case, since the elevator is accelerating downwards, the acceleration due to gravity and the acceleration of the elevator act in the same direction. To find the normal force, we plug in the values into the equation:
N = m(g - a)
N = 65 kg((9.8 m/s²) - (2.4 m/s²))
N = 65 kg(7.4 m/s²)
N ≈ 481 N
Therefore, the scale would read approximately 481 N during this acceleration.
The equation N = m(g + a) represents the forces acting on Jay if we consider the positive direction to be downwards. In this case, the acceleration due to gravity and the elevator's acceleration would act in opposite directions. So, using the equation N = m(g + a) would give us an incorrect result in this situation.