Answer: D
Explanation:
When an object falls gravity is pulling down on it and is picking up speed, but as it gains speed air resistance becomes a faster. Air resistance increases with speed. And that force keeps it from accelerating eventually the object will pick up speed such that the force due to air resistance will keep it from getting any more speed at that point force due to air resistance is equal to its weight (mg) and the net force is equal to zero so it won’t accelerate any more at that point it is said to be moving in terminal velocity.
When an object has reached terminal velocity, it will have a constant velocity
Answer:
speed and direction
Explanation:
Acceleration is the rate of change of speed and direction.
Answer:
Current through each phase Vp = 2.2A
Total three phase power Pt= 1.45kW
Power factor of the load pf = 1
Explanation:
i) Find current through each phase
Vp =220V (rms)
Z =100 Ω
I = Vp/Z
= 220/100
= 2.2A
ii) Find the total three phase power
for a resistive load, Power, P = VI
Power for each phase is given as:
P = 220 * 2.2
= 484 W
Total power TP =3* P
=484*3
= 1452W
=1.45kW
iii) Find the power factor of the load
Phase angle for a resistive load is 0.
α= 0
Hence, power factor of load = cos α
pf = cos 0
pf = 1
Centripetal force is equal to (mv^2)/r
The way I use to answer these question is to set every variable to 1
m=1
v=1
r=1
so centripetal force =1
then change the variable we're looking at
and since we're find when it's half we could either change it to 1/2 or 2, but 2 is easier to use
m=1
v=2
r=1
((1)×(2)^2)/1=4
So the velocity in the 1st part is half the velocity in the 2nd part and the centripetal force is 4× less
The answer is the centripetal force is 1/4 as big the second time around
