Tag: substances, objects and energy

Quizzes (5) Questions (175)

Questions Related to substances, objects and energy

Multiple choice physics types of energy renewable and non-renewable resources renewable and non-renewable sources of energy substances, objects and energy

Select the best definition of mechanical energy?

  1. Energy possessed by an object due to its location or motion

  2. Energy possessed by an object due to its temperature

  3. Energy possessed by an object due to its magnetic property

  4. Energy of an object due to its concentration

  5. Energy possessed by an object due to its age
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mechanical energy is the energy that is possessed by an object due to its motion or due to its position. Mechanical energy can be either kinetic energy(energy of motion) or potential energy (stored energy of position). 

Multiple choice physics types of energy renewable and non-renewable resources renewable and non-renewable sources of energy substances, objects and energy

What is the relationship between the kinetic energy($K$), potential energy($P$) and total energy($E$) of a system?

  1. $K=P+E$
  2. $E=P+K$
  3. $P=K+E$
  4. $E=PK$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Total mechanical energy of the system is equal to the sum of kinetic energy of the system and the potential energy of the system.

Thus, total mechanical energy  $E = K+P$

Multiple choice physics types of energy renewable and non-renewable resources renewable and non-renewable sources of energy substances, objects and energy

A body of mass $15\ kg$ is raised from certain depth. If the work done in raising it by $10m$ is $1620J$, its velocity at this position is$(g=10 { ms }^{ -2 })$:

  1. ${ 2\ ms }^{ -1 }$
  2. ${ 4\ ms }^{ -1 }$
  3. ${ 1\ ms }^{ -1 }$
  4. ${ 8\ ms }^{ -1 }$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

work done=PE+KE

$1620=mgh+\dfrac{mv^2}{2}$
$1620=15\times 10\times 10+\dfrac{15v^2}{2}=1500+\dfrac{15v^2}{2}$
$v=4m/s$

Multiple choice physics types of energy renewable and non-renewable resources renewable and non-renewable sources of energy substances, objects and energy

A body of mass 5 kg falls from a height of
30 metre. If its all mechanical energy is changed into heat, then heat produced
will be:-

  1. 350cal

  2. 150 cal

  3. 60cal

  4. 6cal
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
work done $=mgn$
$= 5 \times 9.8 \times 30 = 14705$
Heat produce $=\dfrac{1470}{4.2}= \boxed{350\ cal}$
$\boxed {Answer\ is\ A}$



























Multiple choice physics types of energy renewable and non-renewable resources renewable and non-renewable sources of energy substances, objects and energy

In a hydroelectric power plant ___ energy is converted into ____ energy.

  1. Chemical into electrical

  2. Chemical into mechanical

  3. Mechanical into electrical

  4. Electrical into mechanical
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In hydroelectric power plant following sequence of energy transformation take place, 

Kinetic energy of water to potential energy of water to mechanical energy of turbine to electric energy through generator.
So among the options given best possible answer is option C.