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Arshak Shan
Subject: Physics
, asked on 1/5/18
a 1kg hockey puck travelling at 2m/s collides with a 2kg hockey puck. the two pucks fly apat after the collision what is the velocity of 2kg puck
Answer
1
Lavneesh Rajput
Subject: Physics
, asked on 27/4/18
A particle is rotated in a vertical circle by connecting it to a string of length l and keeping the other end of the string fixed. The minimum speed of the particle hen the string is horizontal for which the particle ill complete the circle is
$\left(a\right)\sqrt{gl}\phantom{\rule{0ex}{0ex}}\left(b\right)\sqrt{2gl}\phantom{\rule{0ex}{0ex}}\left(c\right)\sqrt{3gl}\phantom{\rule{0ex}{0ex}}\left(d\right)\sqrt{5gl}$
Answer
1
Laieeqa
Subject: Physics
, asked on 17/4/18
Solve this:
Q.12. A metallic wire of 1 m length has a mass of 10
$\times {10}^{-3}$
kg. If a tension of 100 N is applied to a wire, what is the speed of transverse wave?
(1) 100 m
${s}^{-1}$
(2) 10 m
${s}^{-1}$
(3) 200 m
${s}^{-1}$
(4) 0.1 m
${s}^{-1}$
Answer
1
Isha Dixit
Subject: Physics
, asked on 16/4/18
two spring have force constant k1 and k2 (k1 > k2).on which spring is more work done if,
a) they are stretched by the same force and
b) they are stretched by the same amount
Answer
1
Manasi Mujumdar
Subject: Physics
, asked on 13/4/18
31. The capacitance of a parallel plate capacitor with air as dielectric is C. If a slab of dielectric constant
K and of the same thickness as the separation between the plates is introduced so as to fill 1/4
^{th}
of the
capacitor (shown in figure), then the new capacitance is
$\left(a\right)(K+2)\frac{C}{4}\phantom{\rule{0ex}{0ex}}\left(b\right)(K+3)\frac{C}{4}\phantom{\rule{0ex}{0ex}}\left(c\right)(K+1)\frac{C}{4}\phantom{\rule{0ex}{0ex}}\left(d\right)Noneofthese$
Answer
1
Anjudha
Subject: Physics
, asked on 11/4/18
Q.33. A cubical vessel of height 1 m is full of water. What is the amount of work done in pumping water out of the vessel? (Take g = 10 m
${s}^{-2}$
)
(a) 1250 J
(b) 5000 J
(c) 1000 J
(d) 2500 J
Answer
1
Adarsh Agrawal
Subject: Physics
, asked on 4/4/18
Q.32:
32. An engine develops 10KW of power. How much time will it take to lift a mass of 200kg to a height of 40m. (g=10ms
^{-2}
)
1) 4s 2) 5s 3) 8s 4) 10s
Answer
2
Adarsh Agrawal
Subject: Physics
, asked on 4/4/18
Solve this:
Q15. A 2kg body is dropped from height of 1m onto a spring of spring constant 800 N/m as shown in the figure. A frictional force equivalent to 0.4 kg-wt acts on the body. The speed of the body just before striking the spring will be :
1) 1 m/s
2) 2 m/s
3) 3 m/s
4) 4 m/s
Answer
1
Adarsh Agrawal
Subject: Physics
, asked on 4/4/18
Solve this:
22. A body of mass 2 kg is projected vertically up with a velocity of 100 ms
^{-1}
. If it rises to a height of 400 m, the energy utilized to overcome friction is ( g=10 ms
^{-2}
)
1) 10 KJ 2) 8 KJ 3) 1 KJ 4) 2 KJ
Answer
1
Adarsh Agrawal
Subject: Physics
, asked on 4/4/18
Solve this:
27. A body is moving up an inclined plane of angle
$\theta $
with an initial kinetic energy E. The coefficient of friction between the plane and body is
$\mu $
. The work done against friction before the body comes to rest is .
$\left(1\right)\frac{\mu \mathrm{cos}\theta}{E\mathrm{cos}\theta +\mathrm{sin}\theta}\left(2\right)2\mu ECos\theta \phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\left(3\right)\frac{\mu Ec\mathrm{os}\theta}{\mu \mathrm{cos}\theta -\mathrm{sin}\theta}\left(4\right)\frac{\mu Ec\mathrm{os}\theta}{\mu \mathrm{cos}\theta +\mathrm{sin}\theta}$
Answer
1
Adarsh Agrawal
Subject: Physics
, asked on 4/4/18
Solve this:
Q.18. A mason worker throws the bricks to a height of 10 m, at which the bricks reach with a velocity of 6
$m{s}^{-1}$
. The percentage of energy he is wasting is nearly (g = 10 m
${s}^{-2}$
)
1) 15 %
2) 18 %
3) 220 %
4) 36 %
Answer
1
Rajarshi Das
Subject: Physics
, asked on 4/4/18
work energy theorem for constant and variable force
Answer
1
Adarsh Agrawal
Subject: Physics
, asked on 4/4/18
12. A rectangular plank of mass 'm
_{1}
'and height 'a' is on a horizontal surface. On the top of it another rectangular plank of mass
$\text{'}{m}_{2}\text{'}$
and height 'b' is placed. The potential energy of the system is,
$1.\left({m}_{1}+{m}_{2}\right)\frac{\left(a+b\right)}{2}g\phantom{\rule{0ex}{0ex}}2.\left[\frac{{m}_{1}+{m}_{2}}{2}a+{m}_{2}\frac{b}{2}\right]g\phantom{\rule{0ex}{0ex}}3.\left[\left(\frac{{m}_{1}}{2}+{m}_{2}\right)a+{m}_{2}\frac{b}{2}\right]g\phantom{\rule{0ex}{0ex}}4.\left[\left(\frac{{m}_{1}}{2}+{m}_{2}\right)a+{m}_{1}\frac{b}{2}\right]g$
Answer
2
Sunidhi Sarmah
Subject: Physics
, asked on 2/4/18
Question no. 1 please
Q.1. The momentum of a body is given by
$\overrightarrow{P}=\left(10{t}^{2}\hat{i}+5t\hat{j}\right)kg.m./s.$
Find the force acting on the body at t = 2s.
Answer
1
Shreya Choudhary
Subject: Physics
, asked on 30/3/18
Solve this:
Q.23. A ball strikes a horizontal floor normally. One-fourth of its kinetic energy is lost in collision. The coefficient of restitution of the collision is
(1)
$\frac{1}{2}$
(2)
$\frac{\sqrt{3}}{2}$
(3)
$\frac{1}{\sqrt{2}}$
(4)
$\frac{1}{2\sqrt{2}}$
Answer
1
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What are you looking for?

$\left(a\right)\sqrt{gl}\phantom{\rule{0ex}{0ex}}\left(b\right)\sqrt{2gl}\phantom{\rule{0ex}{0ex}}\left(c\right)\sqrt{3gl}\phantom{\rule{0ex}{0ex}}\left(d\right)\sqrt{5gl}$

Q.12. A metallic wire of 1 m length has a mass of 10 $\times {10}^{-3}$ kg. If a tension of 100 N is applied to a wire, what is the speed of transverse wave?

(1) 100 m${s}^{-1}$

(2) 10 m${s}^{-1}$

(3) 200 m${s}^{-1}$

(4) 0.1 m${s}^{-1}$

a) they are stretched by the same force and

b) they are stretched by the same amount

K and of the same thickness as the separation between the plates is introduced so as to fill 1/4

^{th}of thecapacitor (shown in figure), then the new capacitance is

$\left(a\right)(K+2)\frac{C}{4}\phantom{\rule{0ex}{0ex}}\left(b\right)(K+3)\frac{C}{4}\phantom{\rule{0ex}{0ex}}\left(c\right)(K+1)\frac{C}{4}\phantom{\rule{0ex}{0ex}}\left(d\right)Noneofthese$

(a) 1250 J

(b) 5000 J

(c) 1000 J

(d) 2500 J

32. An engine develops 10KW of power. How much time will it take to lift a mass of 200kg to a height of 40m. (g=10ms

^{-2})1) 4s 2) 5s 3) 8s 4) 10s

Q15. A 2kg body is dropped from height of 1m onto a spring of spring constant 800 N/m as shown in the figure. A frictional force equivalent to 0.4 kg-wt acts on the body. The speed of the body just before striking the spring will be :

1) 1 m/s

2) 2 m/s

3) 3 m/s

4) 4 m/s

22. A body of mass 2 kg is projected vertically up with a velocity of 100 ms

^{-1}. If it rises to a height of 400 m, the energy utilized to overcome friction is ( g=10 ms^{-2})1) 10 KJ 2) 8 KJ 3) 1 KJ 4) 2 KJ

27. A body is moving up an inclined plane of angle $\theta $ with an initial kinetic energy E. The coefficient of friction between the plane and body is $\mu $. The work done against friction before the body comes to rest is .

$\left(1\right)\frac{\mu \mathrm{cos}\theta}{E\mathrm{cos}\theta +\mathrm{sin}\theta}\left(2\right)2\mu ECos\theta \phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\left(3\right)\frac{\mu Ec\mathrm{os}\theta}{\mu \mathrm{cos}\theta -\mathrm{sin}\theta}\left(4\right)\frac{\mu Ec\mathrm{os}\theta}{\mu \mathrm{cos}\theta +\mathrm{sin}\theta}$

Q.18. A mason worker throws the bricks to a height of 10 m, at which the bricks reach with a velocity of 6 $m{s}^{-1}$. The percentage of energy he is wasting is nearly (g = 10 m${s}^{-2}$)

1) 15 %

2) 18 %

3) 220 %

4) 36 %

_{1}'and height 'a' is on a horizontal surface. On the top of it another rectangular plank of mass $\text{'}{m}_{2}\text{'}$ and height 'b' is placed. The potential energy of the system is,$1.\left({m}_{1}+{m}_{2}\right)\frac{\left(a+b\right)}{2}g\phantom{\rule{0ex}{0ex}}2.\left[\frac{{m}_{1}+{m}_{2}}{2}a+{m}_{2}\frac{b}{2}\right]g\phantom{\rule{0ex}{0ex}}3.\left[\left(\frac{{m}_{1}}{2}+{m}_{2}\right)a+{m}_{2}\frac{b}{2}\right]g\phantom{\rule{0ex}{0ex}}4.\left[\left(\frac{{m}_{1}}{2}+{m}_{2}\right)a+{m}_{1}\frac{b}{2}\right]g$

Q.1. The momentum of a body is given by

$\overrightarrow{P}=\left(10{t}^{2}\hat{i}+5t\hat{j}\right)kg.m./s.$

Find the force acting on the body at t = 2s.

Q.23. A ball strikes a horizontal floor normally. One-fourth of its kinetic energy is lost in collision. The coefficient of restitution of the collision is

(1) $\frac{1}{2}$

(2) $\frac{\sqrt{3}}{2}$

(3) $\frac{1}{\sqrt{2}}$

(4) $\frac{1}{2\sqrt{2}}$