Answer:
B. When the racket hits the tennis ball with a force, the tennis ball applies an equal but opposite force to the racket.
Explanation:
According to the Newton's third law of motion every action has equal and opposite reaction. So, when the force is applied by the racket on the ball then the ball also applies an equal intensity of force in the opposite direction on the racket. It is just that the the force on the racket is absorbed by the player holding it.
<span>The surface charge density = q/A
So q = surface charge density x Area
The surface area of a sphere of radius R is 4*Pi*R^2. R = d/2 where d is diameter. This leaves us with 1.3/2 = 0.65. Area = 4 * pie * (0.65)^2 = 5.30998.
So the net charge q = 8.1 * 10^(-6) * 5.30998 = 42.47998 * 10^(-6)
The Total electric flux = Q/e_0 where , 8.854 Ă— 10â’12, e_0 is permitivity of free space.
So Flux = 42.47998 * 10^(-6) / 8.854 * 10(â’12) = 4.833 * 10^(-6 - (-12)) = 4.833 * 10^(6)</span>
Answer:
(e) 98,1 KJ
Explanation:
The engine produces 19%; it means, it rejects 81% of energy. ⇒ 81/19=4.26 times.
The engine produces 23 kJ; it means it rejects 23 * 4.26 = 98.05263 kJ
I use the impulse momentum formula.
the 4.0 kilogram ball requires more force to stop
Answer:
86 turns
Explanation:
Parameters given:
Magnetic torque, τ = 1.7 * 10^(-2) Nm
Area of coil, A = 9 * 10^(-4) m²
Current in coil, I = 1.1 A
Magnetic field, B = 0.2 T
The magnetic toque is given mathematically as:
τ = N * I * A * B
Where N = number of turns
To find the number of turns, we make N subject of formula:
N = τ/(I * A * B)
Therefore:
N = (1.7 * 10^(-2)) / (1.1 * 9 * 10^(-4) * 0.2)
N = 85.85 = 86 turns (whole number)
The number of turns must be 86.
