Answer:
A) 0.50 mV
Explanation:
In this problem, we can think the wings of the bird as a metal rod moving across a magnetic field. So, and emf will be induced into the wings of the bird, according to the formula:

where
is the strength of the magnetic field
v = 13 m/s is the speed of the bird
L = 1.2 m is the wingspan of the bird
is the angle between the direction of motion and the direction of the magnetic field
Substituting numbers into the formula, we find

Answer:
B. the force of friction of the road on the tires
Explanation:
Unless the car engine is like jet engine, the main force that accelerates the car forward is the force of friction of the road on the tires, which is ultimately driven by the force of engine on the tires shaft. As the engine, and the shaft are part of the system, their interaction is internal. According to Newton laws of motion, the acceleration needs external force, in this case it's the friction of the road on the tires.
Answer:

Explanation:
As we know that average velocity is defined as the ratio of total displacement of the object and its time interval.
so here we can say

now we know that in one complete revolution the total displacement of the tip of the seconds hand is zero
because it will have same position after one complete revolution from where it starts
so here we can say that the average velocity will be zero

Matt Biondi..?
(I don’t know if it’s right, sorry if it is wrong)
:)