Physics · Science General

Collisions, Momentum and Kinetic Energy

385 Questions

Collisions, momentum, and kinetic energy questions analyze the principles of elastic and inelastic impacts. They require calculating mass, velocity, and conserved energy during physical interactions. These foundational physics topics are essential for most government engineering and general science examinations.

Elastic collisionsInelastic collisionsMomentum calculationKinetic energy principlesVelocity after impact

Collisions, Momentum and Kinetic Energy Questions

Multiple choice collisions in one dimension collisions work, energy and power mechanics physics

A neutron moving with velocity u collides with a stationary $\alpha -particle$ The velocity of the neutron after collision is 

  1. $-\dfrac { 3\cup }{ 5 } $
  2. $\dfrac { 3\cup }{ 5 } $
  3. $\dfrac { 2\cup }{ 5 } $
  4. $-\dfrac { 2\cup }{ 5 } $
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Mass of alpha particle is $4$ times to neutron 
according to the condition alpha paticle is at rest so its velocity is zero
now the final velocity of neutron is calculated from this formula
$U' = (m-1-m _2÷ m _1+m _2) U^1$
by putting$,$ 
$U' = (1-4÷1+4) $
$= -3U/5 $
Negative sign shows reverse direction of neutro$.$
Hence,
option $(A)$ is correct answer.

Multiple choice collisions in one dimension collisions work, energy and power mechanics physics

The principle of conservation of linear momentum can be strictly applied during a collision between two particles provided the time of impact is

  1. Extremely small

  2. Moderately small

  3. Extremely large

  4. Depends on a particular case
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The principle of conservation of linear momentum can be strictly applied during a collision between two particles provided the time of impact is  $Moderately\,\,small.$

Hence,
option $(B)$ is correct answer.

Multiple choice physics measurements and experimentation vernier calliper and screw gauge least count of vernier calliper and screw gauge measurement of length

The percentage error in the measurement of mass and speed are 2% and 3% respectively. The maximum percentage error in the estimation of kinetic energy of a body will be:

  1. 11%

  2. 8%

  3. 5%

  4. 1%
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$K.E = \dfrac{1}{2}mv^{2}$


$ \dfrac{\triangle K.E}{K.E} =

\dfrac{\triangle m}{m} + 2 \dfrac{\triangle v}{v}$

              $ = 2+2(3) = 8$%

Multiple choice physics measurements and experimentation vernier calliper and screw gauge least count of vernier calliper and screw gauge measurement of length

If the error in measurement of momentum of a particle is $10$% and mass is known exactly,the permissible error in the determination of kinetic energy is

  1. $20$%
  2. $5$%
  3. $21$%
  4. $10$%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Kinetic energy K = p^2 / (2m). Since mass is constant, dK/K = 2 * dp/p. With dp/p = 10%, dK/K = 2 * 10% = 20%.

Multiple choice physics measurements and experimentation vernier calliper and screw gauge least count of vernier calliper and screw gauge measurement of length

The speed of a body is measured with a positive error of 30%. If the mass of the body is known exactly, the kinetic energy is calculated with an error of

  1. $60$%
  2. $30$%
  3. $69$%
  4. $39$%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Kinetic energy K = (1/2)mv^2. Since mass is constant, dK/K = 2 * dv/v. Given dv/v = 30%, dK/K = 2 * 30% = 60%.

Multiple choice physics measurements and experimentation vernier calliper and screw gauge least count of vernier calliper and screw gauge measurement of length

Percentage error in the measurement of mass and speed are 2% and 3% respectively. The error in the estimate of kinetic energy obtained by measuring mass and need will be

  1. 12%

  2. 10%

  3. 8%

  4. 2%
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Given percentage errors in mass and velocity = $2$% and $3$% respectively


The kinetic energy of the particle is given by 


$KE$ = $\dfrac { m{ v }^{ 2 } }{ 2 } $

The percentage error in kinetic energy will be

$\dfrac { \Delta m }{ m } \times 100\quad +\quad 2\dfrac { \Delta v }{ v } \times 100$

= $2 + 6$

= $8$% 

Multiple choice physics measurements and experimentation vernier calliper and screw gauge least count of vernier calliper and screw gauge measurement of length

In an experiment, mass of an object is measured by applying a known force on it, and then measuring its acceleration. If, in the experiment, the measured values of applied force and the measured acceleration are $F=10.0\pm 0.2N$ and $a=1.00\pm 0.01m/{s}^{2}$, respectively, the mass of the object is

  1. $10.0Kg$
  2. $10.0\pm 0.1Kg$
  3. $10.0\pm 0.3Kg$
  4. $10.0\pm 0.4Kg$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$F=Ma$
$M=\cfrac { f }{ a } $
$\cfrac { \Delta M\times 100 }{ M } =\cfrac { \Delta f }{ f } \times 100+\cfrac { \Delta a }{ a } \times 100$
$=\cfrac { 0.2 }{ 10 } +\cfrac { 0.01 }{ 1 } $
$\Delta M=0.03\times 10$
$\therefore$ $10.0\pm 0.3Kg$

Multiple choice physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

A body of mass $m =3.513\ kg$ is moving along the x-axis with a speed of $5.00{ ms }^{ -1 }$. The magnitude of its momentum is recorded as :

  1. $17.56\ kg{ ms }^{ -1 }$
  2. $17.57\ kg{ ms }^{ -1 }$
  3. $17.6\ kg{ ms }^{ -1 }$
  4. $17.565\ kg{ ms }^{ -1 }$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Momentum$=mv=3.513\times 5.00=17.565\approx 17.57$
$\approx 17.6 kg m/s$
(Since 5.00 contains  least no. of significant figures i.e. 3)

Multiple choice

What is the famous equation that relates mass and energy?

  1. $E = mc^2$
  2. $E = hv$
  3. $F = ma$
  4. $E = kT$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The equation $E = mc^2$ is one of the most famous and important equations in physics, expressing the equivalence of mass and energy.

Multiple choice

The coefficient of restitution is a measure of the:

  1. Elasticity of a collision

  2. Inelasticity of a collision

  3. Momentum of a collision
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The coefficient of restitution is a dimensionless quantity that measures the elasticity of a collision. It is defined as the ratio of the relative velocity of separation to the relative velocity of approach of the colliding objects. A coefficient of restitution of 1 indicates a perfectly elastic collision, while a coefficient of restitution of 0 indicates a perfectly inelastic collision.

Multiple choice

What is the formula for the kinetic energy of an object?

  1. \(KE = \frac{1}{2} mv^2\)
  2. \(KE = mv\)
  3. \(KE = \frac{1}{2} m^2v\)
  4. \(KE = \frac{1}{2} v^2\)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The formula for the kinetic energy of an object is (KE = \frac{1}{2} mv^2), where (m) is the mass of the object and (v) is its velocity.

Multiple choice

What is the formula for calculating kinetic energy?

  1. $KE = rac{1}{2}mv^2$
  2. $KE = mv$
  3. $KE = m^2v$
  4. $KE = rac{1}{2}m^2v^2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Kinetic energy (KE) is calculated using the formula $KE = rac{1}{2}mv^2$, where 'm' is the mass of the object and 'v' is its velocity.

Multiple choice

According to Newton's Second Law of Motion, the acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to the mass of the object. The equation for Newton's Second Law is:

  1. F = ma

  2. F = mv

  3. F = kx
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Newton's Second Law of Motion states that the acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to the mass of the object. The equation for Newton's Second Law is F = ma, where F is the net force, m is the mass of the object, and a is the acceleration of the object.

Multiple choice

The momentum of an object is defined as the product of its mass and velocity. The equation for momentum is:

  1. p = mv

  2. p = F/t

  3. p = kx
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The momentum of an object is defined as the product of its mass and velocity. The equation for momentum is p = mv, where p is the momentum, m is the mass of the object, and v is the velocity of the object.