Answer:
1) D, 2) D, 3) B, 4) B, 5) C
Explanation:
You are asked to select the correct answer
1) The conservation of energy is one of the most important principles of physics that allows solving countless problems in life.
the correct answer is D
2) when a body falls, the gravitational potential energy is transformed into kinetic energy and both are transformed into thermal energy
the correct answer is D
3) When the gravitational potential energy is maximum, the kinetic energy is minimum and when the kinetic energy is maximum, the gravitational energy is minimum.
Correct answer B
4) speed is defined by
v = x / t
so the correct answer is B in the SI system
5) when we repeat a measurement several times, the random or statistical errors decrease, therefore the confidence of the measurement increases.
The correct answer is C
Two neutral objects will not have any electric force of attraction or repulsion between them.
<h3>What is the condition for the electric force between two objects?</h3>
As we know from the electrostatics that whenever there are two charges having a positive charge on one and a negative on the other will attract each other
similarly, if they are having like charges which are both of them having positive or both of them having a negative charge then there will be a force of repulsion between them.
But if both of them or even one of them is neutral then there will not be any electric force between them.
Thus neutral objects will not have any electric force of attraction or repulsion between them.
To know more about the nature of charged particles follow
brainly.com/question/22492496
Answer:
2.12/R mW
Explanation:
The electrical power, P generated by the rod is
P = B²L²v²/R where B = magnetic field = 0.575 T, L = length of metal rod = separation of metal rails = 20 cm = 0.2 m, v = velocity of metal rod = 40 cm/s = 0.4 m/s and R = resistance of rod = ?
So, the induced emf on the conductor is
E = BLv
= 0.575 T × 0.2 m × 0.4 m/s
= 0.046 V
= 46 mV
The electrical power, P generated by the rod is
P = B²L²v²/R
= B²L²v²/R
So, P = (0.575 T)² × (0.2 m)² × (0.4 m/s)²
= 0.002116/R W
= 2.12/R mW
Answer:
42.417 cm³
Explanation:
The formula to find the volume of a cone is :
V = 
× π r² h
Here,
r ⇒ radius ⇒ 3 cm
h ⇒ height ⇒ 4.5 cm
<u>Let us find it now.</u>
V = × π r² h
V = × π × 3 × 3 × 4.5
V = × π × 9 × 4.5
V = × π × 9 × 4.5
V = × π × 40.5
V = × 3.142 × 40.5
V = × 127.251
V = <u>42.417 cm³</u>
