The Dominating Component

Q. In case of projectile motion, we neglect air resistance. What changes would be there is we take air resistance into consideration?

Q. The two ends $A$ and $B$ of a uniform rod of length $l=1\text{m}$ are moving with velocities $V_A$ and $V_B$ as shown. The velocity $V_B\left(\text{m/s}\right)$ is

Q. a parachutist flying in an aerolane jumps whanit is at a height 3km above the ground.he opens his parachute when he is above ground .describe his motion

Q.

is air resistance dependant of mass of the object?

Q. Trajectories are shown in figure for three footballs. Initially vertical and horizontal velocity components are $u_y$ and $u_x$ respectively. Ignoring air resistance, choose the correct statements from List-II for the value of variable in List-I

$\begin{array}{cccc}& \text{List-I}& & \text{List-II}\\ \text{(I)}& \text{Time of flight}& \text{(P)}& \text{greater for A only}\\ \text{(II)}& \frac{u_y}{u_x}& \text{(Q)}& \text{greater for C only}\\ \text{(III)}& u_x& \text{(R)}& \text{Equal for A and B}\\ \text{(IV)}& u_x{u}_y& \text{(S)}& \text{Equal for B and C}\end{array}$

1. $I\to R;II\to Q;III\to P;IV-S$
2. $I\to R;II\to P;III\to Q;IV-S$
3. $I\to P;II\to R;III\to Q;IV-S$
4. $I\to Q;II\to P;III\to S;IV-R$

Q.

Two bodies are falling with negligible air resistance side by side, above a horizontal plane. If one of the bodies is given an additional horizontal acceleration during its descent, then it

1. Strikes the plane at same time as the other body

2. Strikes the plane before other body strikes

3. follows a straight line path along the resultant acceleration vector

4. None of the above

Q. A ball of mass 0.4kg thrown up in air with velocity 30m/s reaches the highest point in 25 seconds. The air resistance encountered by the ball during upward motion is?

Q. A cannon on a level plane is aimed at an angle $\theta$ above the horizontal and a shell is fired with a muzzle velocity $v_o$ towards a vertical cliff a distance D away. Then the height from the bottom at which the shell strikes the side walls of the cliff is

1. D sin -
2. D cos -
3. D tan -
4. D tan -

Q. I ask to my teacher, "sir, could we travel to stars???"
He said "No man because we didn't have that much of fuel"

But once we leave the escape velocity of earth then the shuttle moves on with same velocity when he released from earth escape layer...
Then why we need fuel for travel in space to go to stars......

Q. The trajectory of a projectile in a vertical plane is $y=ax-{bx}^2$, where $a$, $b$ are constants, and $x$ and $y$ are, respectively, the horizontal and vertical distance of the projectile from the point of projection. The maximum height attained is ________ and the angle of projectile from the horizontal is _______.

Q.

When we throw an object while a hot air balloon is descending, does the object go up or down?

Q. Oblique projectile motion is asymmetric because we have a component of acceleration due to gravity parallel to an inclined plane.

1. True
2. False

Q. A ball is thrown with velocity 10m/sec . Then find time of flight assuming no air resistance .

Q. Trajectories are shown in figure for three footballs. Initially vertical and horizontal velocity components are $u_y$ and $u_x$ respectively. Ignoring air resistance, choose the correct statements from List-II for the value of variable in List-I

$\begin{array}{cccc}& \text{List-I}& & \text{List-II}\\ \text{(I)}& \text{Time of flight}& \text{(P)}& \text{greater for A only}\\ \text{(II)}& \frac{u_y}{u_x}& \text{(Q)}& \text{greater for C only}\\ \text{(III)}& u_x& \text{(R)}& \text{Equal for A and B}\\ \text{(IV)}& u_x{u}_y& \text{(S)}& \text{Equal for B and C}\end{array}$

1. $I\to R;II\to Q;III\to P;IV-S$
2. $I\to R;II\to P;III\to Q;IV-S$
3. $I\to P;II\to R;III\to Q;IV-S$
4. $I\to Q;II\to P;III\to S;IV-R$

Q. A cannon on a level plane is aimed at an angle $\theta$ above the horizontal and a shell is fired with a muzzle velocity $v_o$ towards a vertical cliff a distance D away. Then the height from the bottom at which the shell strikes the side walls of the cliff is

1. D sin $\theta$ -$\frac{g{D}^2}{2v_0^{2}si{n}^2\theta }$
2. D cos $\theta$ - $\frac{g{D}^2}{2v_0^{2}co{s}^2\theta }$
3. D tan $\theta$ - $\frac{g{D}^2}{2v_0^{2}co{s}^2\theta }$
4. D tan $\theta$ - $\frac{g{D}^2}{2v_0^{2}si{n}^2\theta }$

Q. Consider two stones $\text{A}\&\text{B}$ which are being projected as shown with speeds $20\text{m/s}$ and $40\text{m/s}$ respectively as seen by a stationary observer on ground. Find the time when they meet.

1. $1\text{s}$
2. $2\text{s}$
3. $3\text{s}$
4. $4\text{s}$

Q. A cannon on the level plane is aimed at an angle $\theta$ above the horizontal and a shell is fired with a muzzle velocity $v_o$ towards the vertical cliff at a distance $R$ away. The height from the bottom at which the shell strikes the side walls of the cliff is

1. $R\tan \theta -\frac{g{R}^2}{2{v_o}^2{\cos }^2\theta }$
2. $R\tan \theta -\frac{g{R}^2}{2{v_o}^2}$
3. $R\tan \theta +\frac{g{R}^2}{2{v_o}^2{\cos }^2\theta }$
4. $R\tan \theta -\frac{g{R}^2}{2{v_o}^2{\sin }^2\theta }$

Q.

when more no of tyres are provided on aheavy truck to didtribute the pressure of its heavy loads then why small wheels are provided in areoplane which also carries a large no of passengers?

Q. A rocket is fired at a velocity of $80m/s$ from the ground level at an angle of $50$ degrees above the horizontal. The rocket is fire toward an $10m$ high wall, which is located $20m$ away. By how much does the rocket clear the top of the wall? (in m)

1. $15$
   
2. $13.2$
   
3. $13$
   
4. $12$
   

Q.

A person standing on the top of a cliff, $171ft$ high, has to throw a packet to his friend standing on the ground 228 ft horizontally away. If he throws the packet directly aiming at the friend with a speed of $15.0ft/s$, how short will the packet fall? Give $g$ = $32ft/s^2$.

1. 36 feet

2. 12 feet

3. 0 feet the packet reaches his friend

4. 192 feet

Q.

A man is sitting on the shore of a river. He is in the line of a 1.0 m long boat and is 5.5 m away from the center of the boat. He wishes to throw an apple into the boat. If he can throw the apple only with a speed of 10 m/s, find the minimum and maximum angles of projection for successful shot. Assume that the point of Projection and the edge of the boat are in the same horizontal level.

1. ${15}^{\circ }$, ${75}^{\circ }$

2. ${18.5}^{\circ }$, ${75}^{\circ }$

3. ${15}^{\circ }$, ${71.5}^{\circ }$

4. ${18.5}^{\circ }$, ${71.5}^{\circ }$

Q. A ball is projected from ground with speed 10 m/s, then the minimum angle of projection so that the ball lands on the 2nd stair is

1. ${10}^{\circ }$
2. ${30}^{\circ }$
3. ${15}^{\circ }$
4. ${7.5}^{\circ }$

Q. 15 State and prove Snells law

Q. Trajectories are shown in figure for three footballs. Initially vertical and horizontal velocity components are $u_y$ and $u_x$ respectively. Ignoring air resistance, choose the correct statements from List-II for the value of variable in List-I

$\begin{array}{cccc}& \text{List-I}& & \text{List-II}\\ \text{(I)}& \text{Time of flight}& \text{(P)}& \text{greater for A only}\\ \text{(II)}& \frac{u_y}{u_x}& \text{(Q)}& \text{greater for C only}\\ \text{(III)}& u_x& \text{(R)}& \text{Equal for A and B}\\ \text{(IV)}& u_x{u}_y& \text{(S)}& \text{Equal for B and C}\end{array}$

1. $I\to R;II\to Q;III\to P;IV-S$
2. $I\to R;II\to P;III\to Q;IV-S$
3. $I\to P;II\to R;III\to Q;IV-S$
4. $I\to Q;II\to P;III\to S;IV-R$