Tag: moving things around us

Questions Related to moving things around us

Multiple choice physics kinematics motion around us motion and rest moving things around us

Two balls of different masses have the same KE. Then the: 

  1. Heavier ball has greater momentum than the lighter ball.

  2. Lighter Will has greater momentum than the heavier ball.

  3. Both bans have equal momentum.

  4. Both balls have zero momentum.

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The relation between kinetic energy $(K)$ and momentum $(p)$ is given by, $K=\dfrac{p^2}{2m}$ where $m$ be the mass of the body

So, $p=\sqrt{2mK}$
As kinetic energy is constant, so $p\propto \sqrt m$
Thus, the heavier ball has more momentum than that of lighter ball. 

Multiple choice physics kinematics motion around us motion and rest moving things around us

When a body is at rest, it is obeying

  1. Principle of conservation of energy

  2. Principle of moments

  3. Newton's first law

  4. Newton's second law

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Inertia is the tendency of an object to remain at rest or in motion. Newton's First Law of Motion states that an object will remain at rest or move at a constant speed in a straight line unless it is acted on by an unbalanced force.
So, when a body is at rest, it is obeying Newton's first law or motion or law of inertia. 
Multiple choice physics along with motion motion around us motion and rest moving things around us

What is corrct statement about impulse?

  1. change in velocity

  2. change in momentum due to force in small time

  3. change in acceleration

  4. change in speed

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Impulse:- It is defined as a change in momentum due to force in small time.

Mathematically, 
From Newton's law,
$F=\dfrac{\Delta p}{\Delta t}$
Impulse, $I=F\times \Delta t=\Delta P$
The correct option is B.

Multiple choice physics along with motion motion around us motion and rest moving things around us

A train of length 200 m traveling at $30 { ms }^{ -1 }$ overtakes another train of length 300 m traveling at $20 { ms }^{ -1 }$. The time taken by the first train to pass the second is 

  1. 10 s

  2. 30 s

  3. 40 s

  4. 50 s

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The relative speed of the first train with respect to the second is 30 - 20 = 10 m/s. The total distance to be covered to overtake is the sum of the lengths of both trains: 200 + 300 = 500 m. Time = Distance / Relative Speed = 500 / 10 = 50 s.

Multiple choice physics along with motion motion around us motion and rest moving things around us

 A person in a car tends to fall back when it suddenly starts. It is due to

  1. Inertia of rest

  2. Inertia of motion

  3. Inertia of direction

  4. none

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

when bus suddenly start moving in forward direction. This happens due to. When a bus suddenly starts, the standing passengers fall backward in the bus.

It is due to inertia of rest.
Hence,

option $A$ is correct answer.

Multiple choice physics along with motion motion around us motion and rest moving things around us

The wall of your classroom is in a state of -

  1. motion

  2. rest

  3. neither rest nor motion

  4. none of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The walls are at rest with respect to the Earth. When you are sitting in the classroom, you are also at rest with respect to the Earth, and so the walls do not seem to be moving to you.

Multiple choice physics along with motion motion around us motion and rest moving things around us

If the forces acting on an object are balanced, then_____

  1. the object will be in equilibrium

  2. the object will be in motion

  3. the object will have zero acceleration

  4. the object loses its shape

Reveal answer Fill a bubble to check yourself
A,C Correct answer
Explanation

according to newton's first law of motion, an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

so if forces acting on the object is balanced then the object will be in equilibrium and it will not have any acceleration.
cannot comment about option B because if initially object is at rest then it will be always at rest .
so best possible answer are option A,C.

Multiple choice physics along with motion motion around us motion and rest moving things around us

If $\vec {u}=a \hat {i}+b \hat {j}+ c \hat {k}$ with $\hat {i},\hat {j},\hat {k}$ are in east, north and vertical directions, the maximum height of the projectile is ?

  1. $\dfrac{a^{2}}{2g}$

  2. $\dfrac{b^{2}}{2g}$

  3. $\dfrac{c^{2}}{2g}$

  4. $\dfrac{b^{2} c^{2}}{2g}$

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The maximum height of a projectile is H = (vertical component of velocity)²/(2g). If vector u = aî + bĵ + cĵ with î east, ĵ north (horizontal), and ĵ vertical, then the vertical component of initial velocity is c (assuming cĵ represents the vertical direction, which typically uses the unit vector k̂, but in this notation cĵ or ck̂ would give the vertical component c). Maximum height = c²/(2g).

Multiple choice physics kinematics motion around us motion and rest moving things around us

When a body is at rest, it is obeying :

  1. Principle of conservation of energy

  2. Newton's first law

  3. Ohm's law

  4. Newton's second law

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Newton's first law states that; "An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force".Thus, body continues in it's state of rest as there is no external force on it,

So, option B is correct.