Answer:
A.) V = 14 m/s
B.) h = 36.6 m
Explanation:
Given the formula v = √2gh
where g = 9.8m/sec^2 is the acceleration due to gravity.
A.) Determine the impact velocity for an object dropped from a height of 10 m.
Substitute height h in the given formula
V = √2gh
V = √2 × 9.8 × 10
V = √196
V = 14 m/s
b. Determine the height required for an object to have an impact velocity of 26.8 m/sec (~ 60 mph). Round to the nearest tenth of a meter.
Substitute the velocity in the given formula and make height h the subject of formula.
26.8 = √2 × 9.8 × h
Square both sides
718.24 = 19.6h
h = 718.24 / 19.6
h = 36.64 m
h = 36.6 m
Back emf is 85.9 V.
<u>Explanation:</u>
Given-
Resistance, R = 3.75Ω
Current, I = 9.1 A
Supply Voltage, V = 120 V
Back emf = ?
Assumption - There is no effects of inductance.
A motor will have a back emf that opposes the supply voltage, as the motor speeds up the back emf increases and has the effect that the difference between the supply voltage and the back emf is what causes the current to flow through the armature resistance.
So if 9.1 A flows through the resistance of 3.75Ω then by Ohms law,
The voltage across the resistance would be
v = I x R
= 9.1 x 3.75
= 34.125 volts
We know,
supply voltage = back emf + voltage across the resistance
By plugging in the values,
120 V = back emf + 34.125 V
Back emf = 120 - 34.125
= 85.9 Volts
Therefore, back emf is 85.9 V.
This relationship was first published by Sir Issac Newton. His law of universal gravitation says that the force (F) of gravitational attraction between two objects with Mass1 and Mass2 at distance D is: F = G(mass1*mass2)/D squared
Answer: It is selling like crazy! When the Food and Drug Administration asked for scientific proof that the water actually does what it claims to do,
Explanation: