Download App

4.1 , newtons laws of motion — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysics4.1 , newtons laws of motion1 Mark
MCQ
$Assertion$ : A rocket moves forward by pushing the surrounding air backwards.

$Reason$ : It derives the necessary thrust to move forward according to Newton’s third law of motion

  • ✓
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • C
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.
✓

Answer

Correct option: A.
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
a
A rocket moves forward taking the help of reaction force. For that it has to exert a force on the surrounding air so that it receives reaction force as per Newton’s third law.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 4.1 , newtons laws of motion→4.1 , newtons laws of motion — all question types→Physics STD 11 Science question papers→Rajasthan Board STD 11 Science question papers→Rajasthan Board question paper generator→

Similar questions

In an octagon $ABCDEFGH$ of equal side, what is the sum of $\overrightarrow{ AB }+\overrightarrow{ AC }+\overrightarrow{ AD }+\overrightarrow{ AE }+\overrightarrow{ AF }+\overrightarrow{ AG }+\overrightarrow{ AH }$ if, $\overrightarrow{ AO }=2 \hat{ i }+3 \hat{ j }-4 \hat{ k }$
→
The work done on a particle of mass $m$ by a force, $k\left[\frac{x}{\left(x^2+y^2\right)^{3 / 2}} \hat{i}+\frac{y}{\left(x^2+y^2\right)^{3 / 2}} \hat{j}\right]$ ( $K$ being a constant of appropriate dimensions), when the particle is taken from the point $(a, 0)$ to the point $(0, a )$ along a circular path of radius a about the origin in the $x$-y plane is :
→
A block of mass $10\, kg$ is placed on an inclined plane. When the angle of inclination is $30°$, the block just begins to slide down the plane. The force of static friction is ....... $kg\, wt$
→
A diatomic gas of molecular mass $40 \,g / mol$ is filled in a rigid container at temperature $30^{\circ} C$. It is moving with velocity $200 \,m / s$. If it is suddenly stopped, the rise in the temperature of the gas is .........
→
A tunnel is dug in the earth across one of its diameter. Two masses $‘m’\,\& \,‘2m’$ are dropped from the ends of the tunnel. The masses collide and stick to each other and perform $S.H.M.$ Then amplitude of $S.H.M.$ will be : [$R =$ radius of the earth]
→
A rigid body can be hinged about any point on the $x$ -axis. When it is hinged such that the hinge is at $x$, the moment of inertia is given by $I = 2x^2 - 12x + 27$ The $x$ -coordinate of centre of mass is
→
Two gases have the same initial pressure, volume and temperatue. They expand to the same final volume, one adiabatically and the other isothermally
→
$Assertion :$ Mean free path of a gas molecules varies inversely as density of the gas.
$Reason :$ Mean free path varies inversely as pressure of the gas.
→
$Assertion$ : The driver in a vehicle moving with a constant speed on a straight road is an inertial frame of reference.

$Reason$ : A reference frame in which Newton's laws of motion are applicable is non-inertial

→
According to kinetic theory of gases the r.m.s. velocity of the gas molecules is directly proportional to:
→