Definition of a Projectile

Q. A particle is projected vertically upwards with a speed of\sqrt{gR} from earths surface. The maximum height attained by it is (Where R is the radius of earth) Options: a- R/2 b- R c-2R d- R/4

Q. If an object is projected vertically upwards with speed, half the escape speed of earth, then the maximumheight attained by it is \lbrack R is radius of earth\rbrack27(2)(3) 2 R(4)3Rl2RS

Q.

A ball is thrown vertically upward. At the highest point in its path, which of the following statements is correct?

1. The velocity and acceleration are both zero

2. The acceleration is zero and the velocity is pointing down

3. The velocity is zero and the acceleration is pointing down

4. The acceleration is zero and the velocity is pointing up

Q. A missile is fired for maximum range with an initial { velocity of 20m/s . If g=10m/s^2 , the range of the missile is

Q. A small particle of mass m is projected at an angle θ with the X – caxis with an initial velocity v0 in the X – Y plane as shown in the figure. At a time $t=\frac{v_{0}sin\theta }{g}$ the angular momentum of the particle is


Where, $\hat{i}$ $\hat{j}$ and $\hat{k}$ are unit vectors along X, Y and Z-axis respectively.

1. 
2. -
3. 
4. 

Q. If two particles of masses m_1 and m_2 are projected vertically upwards with speeds v_1 and v_2, then the acceleration of the centre ofmass of the system is

Q. A body is projected horizontally from top of A tall tower with velocity v. The velocity at the moment when horizontal and vertical displacement become equal

Q. 130.A very small groove is made in the earth and a particle of mass m0 is placed at a distance R/2 from the centre.Find the escape energy of the particle from that place.

Q.

Escape velocity is:

1. The minimum velocity with which the body has to be projected vertically upwards from the surface of the earth so that it crosses the gravitational field of earth and returns back.

2. The minimum velocity with which the body has to be projected vertically upwards from the surface of the earth so that it crosses the gravitational field of earth and never returns back on its own.

3. The maximum velocity with which the body has to be projected vertically upwards from the surface of the earth so that it crosses the gravitational field of earth and never returns back on its own.

4. The maximum velocity with which the body has to be projected vertically upwards from the surface of the earth so that it crosses the gravitational field of earth and returns back.

Q. 98. A machine gun fires 120 bullets per minute each of mass 50g with a speed of 400m/s . The power of machine gun is

Q. (A body is projected vertically upwards at timet 0.The time corresponding to height h, while ascendingand descending are t-4 s andt 6 s respectively.Then height h is (g= 10 m/s2) (1) 100m (2) 50 m(4) 80 (3) 120 m

Q. A ball of mass m moves with speed v and strikes a wall having infinite mass and it returns with same speed then the work done by the ball on the wall is

Q. A particle of mass m is fired vertically upward with speed v0 (v0 < escape speed). Then the maximum height attained by the particle is

Q. A 40 kg boy swinging on a string the power delivered by gravity force is, when the swing is making an angle 30 with horizontal and the boy moving with a velocity of 8m/s upwar

Q. A: Power of the gravitational force on the body ina projectile motion is zero, once during itsmotion.R At the highest point only, the component ofvelocity along the gravitational force is zero.

Q. three bodies are projected from towers of same height . 1st one is projected vertically up with a velocity u . the second one is thrown down vertically with the same velocity and the third one is dropped as a freely falling body. if t1, t2. t3 are the time taken by them to reach the ground then find a) velocity of projection. b) height of tower c) time taken to free fall in the 3rd case.

Q. The torque about the point of projection of a projectile, when the velocity of particle becomes perpendicular to the direction of initial velocity, is 1. mu2sin theta 2. mu2 cos theta 3. mu2 tan theta 4. mu2 cot theta

Q. A gun is firing bullets with velocity $v_0$ at the same angle with horizontal by rotating throught ${360}^{\circ }$ in the horizontal plane. the maximum area covered by the bullets is :

1. 

2. 

3. 
4. 

Q. 43.speed u at an angle theeta with the horizontal. The average velocity of the projectile between the instants it crosses the same level is

Q.

Which statement is true for a ball thrown at 20 degrees with the horizontal, when it is at the highest point in its trajectory?

1. Its velocity is zero but its acceleration is nonzero

2. Its velocity is perpendicular to its acceleration

3. Its velocity and acceleration are both zero

4. Its velocity is nonzero but its acceleration is zero

Q. the position of an object which is moving in x-y plane is given by \overrightarrow r =3t\overrightarrow i+(2-2t^{})\overrightarrow j then the equation of yrajectory of this object will be

Q. 89.A body is projected vertically up. At certain hight h above the ground, its PE and KE are in ratio 1:4 . At what height above the ground , PE and KE will be in the ratio 4:1

Q. A particle is projected with velocity 10m/s at an angle of 60 degrees from ground. Then the vertical component of velocity vector when instantaneous velocity becomes perpendicular to initial velocity, is

Q. An object is thrown vertically upwards with 20mpersec . Find time taken to reach highest point

Q. 14. A body is projected vertically upwards from the surface of a Planet of radius R with a velocity equal to half the escape velocity for that planet the maximum height attained by the body is

Q. A body is projected vertically upwards with a speed of 40m/s. What is the time taken for it to return to its initial position?

Q. Inspired by Tokyo Olympics, 2020 gold medalist, Neeraj Chopra, Raman decides to take up javelin throw as sports. In one of the practice sessions, Raman throws the javelin at an angle of 37° with the horizontal, with a speed of 15 m/s. The distance from Raman, where the javelin would land is (g = 10 m/s² and neglect the height of Raman)

टोक्यो ओलंपिक 2020 के स्वर्ण पदक विजेता, नीरज चैपड़ा से प्रेरित होकर, रमन ने भाला फेंकने वाले खेल को अपनाने का निश्चय किया। एक अभ्यास सत्र में, रमन भाले को क्षैतिज के साथ 37° कोण पर 15 m/s की चाल से फेंकता है। जहाँ पर भाला गिरेगा, उस स्थान से रमन की दूरी है (g = 10 m/s² तथा रमन की ऊँचाई को नगण्य मानिए)

1. 29.8 m
2. 21.6 m
3. 39.2 m
4. 42 m
   

Q.

Two stones of different masses are thrown vertically upward with same initial velocity. Which one will rise to a greater height?

1. Both will rise to the same height

2. Information given is insufficient

3. Stone of higher mass

4. Stone of lower mass

Q. Two springs A and B, having force constant KA and KB (KA = 3KB) are stretched by applying equal forces. If energy stored in A is E, then that in B is 1)E/3 2)E 3)3E 4)9E

Q. A projectile is given an initial velocity of (α i+β j)m/s where i is along the ground and j along the vertical. the trajectory is