MCQ
The range of a projectile when launched at angle $\theta$ is same as when launched at angle $2 \theta$. What is the value of $\theta$ ?
- A$15$
- ✓$30$
- C$45$
- D$60$
✓
Answer
Correct option: B.
$30$
b
(b)
(b)
$2 \theta=90^{\circ}-\theta$
or $3 \theta=90^{\circ} \text { or } \theta=30^{\circ}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A stone is dropped from a certain height and at the same time another stone is thrown horizontally from the same height which one will reach the ground earlier:
If the temperature of the sun (black body) is doubled, the rate of energy received on earth will be increased by a factor of
If heat is supplied to a solid, its temperature:
- Must increase.
- May increase.
- May remain constant.
- May decrease.
When a gas expands adiabatically
If $P = \frac{{{A^3}}}{{{B^{5/2}}}}$ and $\Delta A$ is absolute error in $A$ and $\Delta B$ is absolute error in $B$ then absolute error $\Delta P$ in $P$ is
→A student is experimenting with resonance tube apparatus in Physics lab to find the speed of sound at room temperature. He got first two resonating lengths of air column as $17\, cm$ and $51 \,cm$, using tuning fork of frequency $512\, Hz$. Find speed of sound at room temperature ..... $m/s$
→An athlete completes one round of a circular track of radius $R$ in $40 \,sec$. What will be his displacement at the end of $2 \,min$. $20 \,sec$
→If $l_1$ and $l_2$ are the lengths of air column for the first and second resonance when a tuning fork of frequency $n$ is sounded on a resonance tube, then the distance of the displacement antinode from the top end of the resonance tube is:
→The force-time $(F -t) $ curve of a particle executing linear motion is as shown in the figure. The momentum acquired by the particle in time interval from zero to $8$ second will be ........... $N-s$
→A household refrigerator with a coefficient of performance $1.2$ removes heat from the refrigerated space at the rate of $60\ kJ/min$ .What would be cost of running this fridge for one month $\mathrm{Rs.}$ ..................... $(30\ days)$ (assuming each day it is used for $4$ hours and cost of one electrical unit is $6$ Rs.)
→