Answer:
F = M a is the vector equation involved
F = T - M g are the forces acting on the elevator (scalar equation)
T - M g = M a
T = M (a + g) remember this a scalar
If a is slowing down then it must have a positive acceleration upwards
Therefor the tension in the cable must be greater than zero
When the tension increases to M g, a has increased to zero
For a to be zero, no acceleration, T = M g
I’m assuming D because it’s the most reasonable
Answer:
The maximum height a person's brain could be above his heart is: 1.28 meter.
Explanation:
We need to know what is the normal blood pressure ours hearts so there is a rate: 120/80 (mmHg) and the average will be: 100 (mmHg) and using the Pascal law that relate pressure, density, gravity and height like:
, where P is pressure, p is density, g is the gravity acceleration and h is the height. Now we can find the height and delta of pressure will be: P2-P1 = 100 (mmHg), knowing that 1(mmHg) is equal to 133 Pa, we can do the convertion to 13332.2 (Pa), now because the units of Pascal are Newton/(meter^2). Then we solve the formula to get the height: 
so we get:
Answer:
t=7.33 s
Explanation:
According to Newton's second law:
because we don't want the box to slide, the acceleration has to be zero.
we know that:
Now having the acceleration, we can use the following formula.
True.
<span>Scientist use conversion factors to express the given value of a unit different type of unit</span>
