### NEET Physics - New - Motion in a Plane

#### Question - 1

A particle moving with velocity $\vec v$ is acted by three forces shown by the vector triangle PQR. The velocitv of the particle will __________

• A Decrease
• B Remain constant
• C Change according to the smallest force $\vec {OR}$
• D Increase

#### Question - 2

When an object is shot from the bottom of a long smooth inclined plane kept at an angle 60o with horizontal, it can travel a distance x1 along the plane. But when the inclination is decreased to 30o and the same object is shot with the same velocity, it can havel x2 distance. Then x1: x2 will be ____________

• A $1: \sqrt{2}$
• B $\sqrt{2}: 1$
• C $1: \sqrt{3}$
• D $1: 2 \sqrt{3}$

#### Question - 3

The ratio of resolving powers of an optical microscope for two wavelength $\lambda_{1}=4000 \text { and } \lambda_{2}=6000$ is ___________

• A 8:27
• B 9:4
• C 3:2
• D 16:81

#### Question - 4

A ship A is moving Westwards with a speed of 10 km h-l and a ship B 100 km South of A is moving Northwards with a speed of l0 km h-l. The time after which the distance between them becomes shortest, is ___________ .

• A 5 h
• B 5$\sqrt 2$ h
• C 10$\sqrt 2$ h
• D 0 h

#### Question - 5

A particle is moving such that its position coordinate (x,y) are
(2m 3m) at time r = 0
(6m, 7m) attime t = 2s and
(13m, 14m) at time r = 5s.
Average velocity vector $\left(\vec{V}_{a v}\right)$ from t = 0 to t = 5s is __________ .

• A $\frac{1}{5}(13 \hat{i}+14 \hat{j})$
• B $\frac{7}{3}(\hat{i}+\hat{j})$
• C $2(\hat{i}+\hat{j})$
• D $\frac{11}{5}(\hat{i}+\hat{j})$

#### Question - 6

Vectors $\vec A,\vec B\ and\ \vec C$ are such that $\vec{A} \cdot \vec{B}=0 \text { and } \vec{A} \cdot \vec{C}=0$ then the vector parallel to $\vec A$is _____________

• A $\vec{B}\ and \ \vec{C}$
• B $\vec{A} \times \vec{B}$
• C $\vec{B}+\vec{C}$
• D $\vec{B} \times \vec{C}$

#### Question - 7

The velocity of a projectile at the initial point A is $(2 \hat{i}+3 \hat{j})$m/s. It's velocity (in m/s) at point.B is ____________

• A $-2 \hat{i}+3 \hat{j}$
• B $2 \hat{i}-3 \hat{j}$
• C $2 \hat{i}+3 \hat{j}$
• D $2 \hat{i}-3 \hat{j}$

#### Question - 8

Aparticle has initial velocity $(2 \vec{i}+3 \vec{j})$ and acceleration $(0.3 \vec{i}+0.2 \vec{j})$. The magnitude of velocity after 10 seconds wiil be ___________ .

• A $9 \sqrt{2}\ units$
• B $5 \sqrt{2}\ units$
• C 5 units
• D 9 units

#### Question - 9

The horizontal range and the maximum height of a projectile are equal. The angle of projection of the projectiles is____________

• A $\theta=\tan ^{-1}\left(\frac{1}{4}\right)$
• B $\theta=\tan ^{-1}(4)$
• C $\theta=\tan ^{-1}(2)$
• D $\theta=45^{\circ}$

#### Question - 10

A projectile is fired at an angle of 45o with the horizontal. Elevation angle of the projectile at its highest point as seen from the point of projection is _______

• A 60o
• B $\tan ^{-1}\left(\frac{1}{2}\right)$
• C $\tan ^{-1}\left(\frac{\sqrt{3}}{2}\right)$
• D 45o