BdPhO Regional (Dhaka-South) : Problemsets

Discuss Physics and Physics Olympiad related problems here
User avatar
SINAN EXPERT
Posts:38
Joined:Sat Jan 19, 2019 3:35 pm
Location:Dhaka, Bangladesh
Contact:
BdPhO Regional (Dhaka-South) : Problemsets

Unread post by SINAN EXPERT » Tue Jan 29, 2019 4:35 pm

$***BdPhO$ $Regional$ $(Dhaka-South)$ $:$ $Secondary***$

$Problem-1$

What will be the reading on the voltmeter? (See the figure)

$Problem-2$

A solid object of mass $4 kg$ is heated at a constant rate $50 W$. The object is kept inside a thermally isolated container so that it cannot radiate heat to the environment. The temperature vs time graph is given. What is the specific latent heat of fusion of the material?

$Problem-3$

A spring of spring constant $k$ with a mass m attached to it has a resonant frequency $f$. If the mass is doubled and the spring constant is changed to $4k$, then express the new resonant frequency $f_n$ in terms of $f$.

$Problem-4$

Consider an isolated system consisted of a ball, and a bucket of water. The ball is released from height, $H$ above a bucket of water. The initial temperature of the water-bucket system and the ball are $T_1$ and $T_2$ respectively. What will be the final temperature of the water after the ball is dropped? (mass of the ball = $m_1$, mass of water = $m_2$, mass of the bucket = $m_3$, specific heat of ball, water and bucket are $s_1$,$s_2$ and $s_3$ respectively)

$Problem-5$

A boy is holding a ball in his hand in a train moving with constant velocity $v$. Then he releases the ball from height $H$ above the floor of the train. What trajectory will the boy see?
If the train moved in a constant acceleration, $a$ what would be the trajectory with respect to the boy? How far in the horizontal direction will the ball hit the floor in this case (according to the reference frame of the train)?

$Problem-6$

A light ray is incident on a rectangular slab $ABCD$ at an angle $θ$ with the normal. The refractive index varies with vertical distance $y$ in the rectangular slab.
Refractive index, $n(y) = ky$, for $0 < y < h$, where $k$ is a constant.
At what angle with the normal the light ray will come out of the surface $AB$?

$Problem-7$

Adventurous Azmain slides down a water slide. He starts with zero initial velocity. The initial point $A$ is at a height $H$ from the ground and the other end $B$ is at a height $h$. The tangent line to the water slide at the point $B$ makes an angle $θ$ with horizontal.
$C$ is the point on ground straight down to point $B$.
How far from the point $C$ does Azmain fall on the ground?

$Problem-8$

Consider two spheres with charge density $+ρ$ and $-ρ$ respectively. The radius of both the spheres is $R$. The centers of the two spheres are at distance $d$ from each other (Here $d<2R$). There is no charge in the intersecting region.
Consider a point $P$ on the line connecting the centers of the two spheres. $P$ is at a distance $x$ from the center of the positively charged sphere (Here $x>R$).
Determine the electric field (magnitude and direction) at $P$.
$The$ $only$ $way$ $to$ $learn$ $mathematics$ $is$ $to$ $do$ $mathematics$. $-$ $PAUL$ $HALMOS$

Post Reply