Answer:
10.15Ω
Explanation:
From ohm's law,
V = IR...................... Equation 1
Where V = Voltage, I = current, R = resistance.
Assume the voltage across the resistance = V,
Given: I = 6.3 A
Substitute into equation 1
V = 6.3R.................. Equation 2
When an additional resistance of 3.4 Ω is inserted in series with R,
The voltage remain the same, but the current changes
Total Resistance(Rt) = (R+3.4)Ω, I' = 4.72 A
Also from ohm' law,
V = I'Rt............... Equation 3
Substitute the value of I' and Rt into equation 3
V = 4.72(R+3.4)............... Equation 5.
Divide equation 2 by equation 5
V/V = 6.3R/4.72(R+3.4)
1 = 1.335R/(R+3.4)
1 = 1.335R/(R+3.4)
R+3.4 = 1.335R
3.4 = 1.335R-R
3.4 = 0.335R
R = 3.4/0.335
R = 10.15Ω
Here is the rule for see-saws here on Earth, and there is no reason
to expect that it doesn't work exactly the same anywhere else:
(weight) x (distance from the pivot) <u>on one side</u>
is equal to
(weight) x (distance from the pivot) <u>on the other side</u>.
That's why, when Dad and Tiny Tommy get on the see-saw, Dad sits
closer to the pivot and Tiny Tommy sits farther away from it.
(Dad's weight) x (short length) = (Tiny Tommy's weight) x (longer length).
So now we come to the strange beings on the alien planet.
There are three choices right away that both work:
<u>#1).</u>
(400 N) in the middle-seat, facing (200 N) in the end-seat.
(400) x (1) = (200) x (2)
<u>#2).</u>
(200 N) in the middle-seat, facing (100 N) in the end-seat.
(200) x (1) = (100) x (2)
<u>#3).</u>
On one side: (300 N) in the end-seat (300) x (2) = <u>600</u>
On the other side:
(400 N) in the middle-seat (400) x (1) = 400
and (100 N) in the end-seat (100) x (2) = 200
Total . . . . . . . . . . . . <u>600</u>
These are the only ones to be identified at Harvard . . . . . . .
There may be many others but they haven't been discarvard.
Answer:
0.5 m/s north
Explanation:
Take east to be +x, west to be -x, north to be +y, and south to be -y.
His displacement in the x direction is:
x = 20 m − 20 m = 0 m
His displacement in the y direction is:
y = 10 m
His total displacement is therefore 10 m north.
His velocity is equal to displacement divided by time.
v = 10 m north / 20 s
v = 0.5 m/s north
Answer:
e. Both the acceleration and net force on the car point inward.
Explanation:
If no net force acts on the car, the car must drive in a straight line, at constant speed.
As the acceleration is defined as the rate of change of the velocity vector, this means that it can produce either a change in the magnitude of the velocity (the speed) or in the direction.
In order to the car can follow a circular trajectory, it must be subjected to an acceleration, that must go inward, trying to take the car towards the center of the circle.
The net force that causes this acceleration, aims inward, and is called the centripetal force.
It is not a different type of force, it can be a friction force, a tension force, a normal force, etc., as needed.
