Answer:
Current in circuit = 2 amp
Explanation:
Given:
Voltage of battery = 10 V
First Resistance R1 = 1 ohm
Second Resistance R2 = 4 ohm
Resistor connected in series
Find:
Current in circuit
Computation;
Resistor connected in series
So,
Total resistance R = First Resistance R1 + Second Resistance R2
Total resistance R = 1 ohm + 4 ohm
Total resistance R = 5 ohm
Current in circuit = V / R
Current in circuit = 10 / 5
Current in circuit = 2 amp
Answer:
B.
It will be greater than 10 J.
Explanation:
The total mechanical energy of an object is the sum of its potential energy (PE) and its kinetic energy (KE):
E = PE + KE
According to the law of conservation of energy, when there are no frictional forces on an object, its mechanical energy is conserved.
The potential energy PE is the energy due to the position of the object: the highest the object above the ground, the highest its PE.
The kinetic energy KE is the energy due to the motion of the object: the highest its speed, the largest its KE.
Here at the beginning, when it is at the top of the roof, the baseball has:
PE = 120 J
KE = 10 J
So the total energy is
E = 120 + 10 = 130 J
As the ball falls down, its potential energy decreases, since its height decreases; as a result, since the total energy must remain constant, its kinetic energy increases (as its speed increases).
Therefore, when the ball reaches the ground, its kinetic energy must be greater than 10 J.
Answer:
Option (C)
Explanation:
The nuclear energy is defined as a type of energy which liberates either by the process of nuclear fusion or nuclear fission and is mainly used to generate electricity. This energy is stored in the core of an atom (or nucleus).
It is highly effective, cost-effective and there is no emission of greenhouse gases.
But it also has some disadvantages, of which one is that it produces radioactive waste materials, which are difficult to dispose these substances and is also a very expensive method. These materials emit radiations that are harmful to the organisms. So, it is very challenging to dispose these radioactive waste materials.
Thus, the correct answer is option (C).
Of the materials listed wood is the best insulator. It would be the least hot if exposed to similar temperatures.
