The equation is derived from the conservation of energy, specifically from potential energy stored at a given height in a gravitational field.
When potential energy is completely converted to kinetic energy you have:
(mv^2)/2=mgh divide both sides by the mass m
v^2/2=gh multiply both sides by 2
v^2=2gh take the square root of both sides
v=√(2gh) and working with imperial units for acceleration due to gravity, g=-32ft/s^2
v=√(-64h) but the change of h as it falls is negative h so
v=-√(64h) so if an object falls from a height of 88ft we have:
v=-√(64*84)
v=-√5376
v≈-73.32 ft/sec (to the nearest hundredth of a foot per second)
Note that this is the velocity, it is negative 73.32 ft/sec.
The question inadvertently asked for velocity and provided answers for SPEED. Velocity is a vector and has both magnitude and direction, whereas speed just has magnitude.
So its final speed is 73.32 ft/sec
So if they actually wanted velocity none of their answers is correct :P
Answer:
x-2x = -3 and x = 3
Step-by-step explanation:
Given the expression
y=x+5.... 1
y-2x=2.... 2
Substituting the first equation into the second we will have;
From 2;
y -2x = 2
x+5-2x = 2
x-2x +5 = 2
x-2x = 2-5
x-2x = -3
-x =-3
x =3
Hence the required equation is x-2x = -3 and x = 3
I have no clue man or woman
