Answer:
A, 30V
Explanation:
First combine all resistors to an equivalent resistor. Since they are in series, the equivalent resistance is the sum of all resistor
Req = 20 + 40 + 60 = 120Ω
Using Ohm's law, find the current in the circuit
V = I * R
I = V / R
I = 60V / 120Ω
I = 0.5 A
Now the potential drop across the resistor R3 is the current times R3 resistance, therefore:
Vdrop = 0.5A * 60Ω = 30V
So the potential drop across resistor R3 is 30 V
Force of gravity on an object is the weight of the object and is given by mass times accerelation due to gravity. The accerelation due to gravity is the accerelation of an object in free fall and is given by 9.8m/s^2. Given that the force of gravity acting on a child's mass on earth is 490 newtns, i.e. F = mg which means that 490 newtons = 9.8 times mass. Therefore, mass of the child is 490 / 9.8 = 50 kg.
Answer:
179.655m
Explanation:
Given
Maximum speed of the arrow v = 60m/s
Time taken to hit the top of the cliff t = 7.0s
Required
Height of the cliff H
Using the equation of motion
H = vt + 1/2gt²
Substitute into the formula:
H = 60(7) + 1/2 (-9.81)(7²) (g is negative due to upward motion of the arrow)
H = 420-4.905(49)
H = 420-240.345
H = 179.655m
Hence the cliff is 179.655m high
<em><u>One</u></em>
Givens
- delta B = 0.20 T/s
- A = 0.07 m^2
- R = 3.5 ohms
Formula
Φ = ΔB*A
e = Φ
Solution (first part)
e = 0.2 * 0.07
e = 0.014 emf
Solution (second part)
i = e/R
i = 0.014 / 3.5
i = 4 * 10^-3
i = 4 ma
Answer
A
<em><u>Two</u></em>
Givens
N = 200 turns
Φ = 30 degrees
Delta B = 0.45 T/s
phi = 30 degrees
r = 0.06 meters
Formula
e = -N * delta B * A * Cos(phi)
Solution
e = -200 * 0.45 (pi r^2) * Cos(30)
e = - 200 * 0.45 * (3.14 * 0.06^2) * cos(30)
e = 0.881 emf
Answer
A
Answer:
Draw a table showing the different forms of the first law for the four processes described.
