It has holes (an electron deficiency).
Answer:
The force of repulsion between the two balls will increase
Explanation:
The electrostatic force between two charged objects is given by
where
k is the Coulomb's constant
q1 and q2 are the charges of the two objects
r is the distance between the centres of the two objects
We see that the magnitude of the force is directly proportional to the charges on the two objects. in this problem, we have two positively charged balls (so, there is a force of repulsion between them, since like charges repel each other and unlike charges attract each other), and the positive charge in one of them is slowly increased: this means that either 
or 
in the formula is increasing, and so the magnitude of the force is increasing.
Answer:
Angular acceleration = 5 rad /s ^2
Kinetic energy = 0.391 J
Work done = 0.391 J
P =6.25 W
Explanation:
The torque is given as moment of inertia × angular acceleration
angular acceleration = torque/ moment of inertia
= 10/2= 5 rad/ s^2
The kinetic energy is = 1/2 Iw^2
w = angular acceleration/time
=5/8= 0.625 rad /s
1/2 × 2× 0.625^2
=0.391 J
The work done is equal to the kinetic energy of the motor at this time
W= 0.391 J
The average power is = torque × angular speed
= 10× 0.625
P = 6.25 W
Answer: person C.
Explanation:
1) The frequency of the sound wave is perceived or detected as the pitch of the sound.
And the higher the frequency the the higher the pitch.
2) When a sound source is in motion there is an apparent change in the pitch perceived. This is the Doppler effect, which is defined as the change in the perception of the pitch in virtue of the relative motion between the listener and the emitter of the sound.
If the source of the sound is moving toward the listener, the pitch will be higher that if the sound is at rest. If the source of the sound is moving away from the listener, the pitch will be lower.
That is because the the motion of the emitter increases (or decreases, depending on whether the emitter is moving toward or away the listener) the speed of the sound waves and they arrive more frequently (or less frequently).
Then, since the sound is emitted by the motorbike and it is moving toward the person C, he will hear the highest pitch.
Answer:
A) mr = 100 kg
B) Fr = 210N
C) Ft = -199.5N
Explanation:
By conservation of the momentum:
mt*Vo = (mr + mt) * Vf Solving for mr:
mr = mt*Vo / Vf - mt = 100 kg
The average force on the receiver:
mr *(Vf - 0) = Fr * Δt Solving for Fr:
Fr = 210 N
The average force on the tackler:
mt * (Vf - Vo) = Ft * Δt Solving for Ft:
Ft = -199.5 N
