MCQ
A projectile is projected with kinetic energy $K$. If it has the maximum possible horizontal range, then its kinetic energy at the highest point will be ......... $K$
  • A
    $0.25$
  • $0.5$
  • C
    $0.75$
  • D
    $1.0$

Answer

Correct option: B.
$0.5$
b
since, range is maximum, therefore $\theta=45^{\circ}$

Hence, $v_{x}=v \cos 45^{\circ}=v / \sqrt{2} .$ At the highest

point, the net velocity of the projectile is

$v_{x}=v \cos 45^{\circ}$

$\therefore \quad \mathrm{KE}=\frac{1}{2} \mathrm{mv}_{\mathrm{x}}^{2}=\frac{1}{2} \mathrm{m} \frac{\mathrm{v}^{2}}{2}=\frac{\mathrm{K}}{2}=0.5 \mathrm{K}$

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

Similar questions

An AC source is rated $222 \,V , 60 \,Hz$. The average voltage is calculated in a time interval of $16.67 \,ms$. It
Figure shows the circular motion of a particle. The radius of the circle, the period, sense of revolution and the initial position are indicated in the figure. The simple harmonic motion of the $x-$ projection of the radius vector of the rotating particle $P$ is
One mole of a monatomic ideal gas is taken along two cyclic processes $E \rightarrow F \rightarrow G \rightarrow E$ and $E \rightarrow F \rightarrow H \rightarrow$ E as shown in the $PV$ diagram. The processes involved are purely isochoric, isobaric, isothermal or adiabatic. $Image$

Match the paths in List $I$ with the magnitudes of the work done in List $II$ and select the correct answer using the codes given below the lists.

List $I$ List $I$
$P.$ $\quad G \rightarrow E$ $1.$ $\quad 160 P_0 V_0 \ln 2$
$Q.$ $\quad G \rightarrow H$ $2.$ $\quad 36 P _0 V _0$
$R.$ $\quad F \rightarrow H$ $3.$ $\quad 24 P _0 V _0$
$S.$ $\quad F \rightarrow G$ $4.$ $\quad 31 P_0 V_0$

Codes: $ \quad  \quad P \quad Q \quad R \quad S $ 

A light string fixed at one end to a clamp on ground passes over a fixed pulley and hangs at the other side. It makes an angle of $30^o$ with the ground. A monkey of mass $5\ kg$ climbs up the rope. The clamp can tolerate a vertical force of $40\ N$ only. The maximum acceleration in upward direction with which the monkey can climb safely is ............ $m/s^2$ (neglect friction and take $g = 10\ m / s^2$ )
Before jumping in water from above, a swimmer bends his body to
A light semi cylindrical gate of radius $R$ is piovted at its mid point $O$, of the diameter as shown in the figure holding liquid of density $\rho $. The force $F$ required to prevent the rotation of the gate is equal to 
Some equipotential surfaces of the magnetic scalar potential are shown in the figure. Magnetic field at a point in the region is
From the given transfer characteristic of a transistor in $CE$ configuration, the value of power gain of this configuration is $10^{ x }$, for $R_B=10\,k \Omega$, and $R _C=1\,k \Omega$. The value of $x$ is $.....$.
In a step-up transformer, turn ratio is $8 : 1$. A $60\,Hz, 120\, volt$ input is connected with its primary coil. Load resistance in secondary coil is $10^4\,\Omega $ Find current in secondry coil.
Which of the following isotopes is used for the treatment of cancer