<u>Answer:
</u>
Cat has 2.02 seconds to right itself.
<u>Explanation:
</u>
Initial height of cat from ground = 20 meter.
We have equation of motion ,
, s is the displacement, u is the initial velocity, a is the acceleration and t is the time.
In this the velocity of cat in vertical direction = 0 m/s, acceleration = acceleration due to gravity = 9.8
, we need to calculate time when s = 20 meter.
Substituting
So, cat has 2.02 seconds to right itself.
Answer:
The correct answers are
(a) It decreases to 1/3 L
(ii) is (c) It is constant
Explanation:
to solve this, we list out the number of knowns and unknowns so as to determine the correct equation to solve the problem
The given variables are as follows
Initial volume V1 = 1L
V2 = Unknown
Initial Temperature T1 = 300K
let us assume that the balloon is perfectly elastic
At 300K the balloon is filled and it stretches to maintain 1 atmosphere
at 100K the content of the balloon cools reducing the excitement of the gas content which also reduces the pressure, however, the balloon being perfectly elastic, contracts to maintain the 1 atmospheric pressure, hence the answer to (ii) is (c) It is constant,
For (i) since we know that the pressure of the balloon is constant
by Charles Law V1/T1 =V2/T2
or V2 = (V1/T1)×T2 =
×
=
× L = L/3 hence the correct answer to (i) is 1/3L
<u>Answer</u>
1) A. 96 Candelas
2) A. Both of these types of lenses have the ability to produce upright images.
3) C. 5 meters
<u>Explanation</u>
Q1
The formula for calculation the luminous intensity is;
Luminous intensity = illuminance × square radius
Lv = Ev × r²
= 6 × 4²
= 6 × 16
= 96 Candelabra
Q2
For converging lenses, an upright image is formed when the object is between the lens and the principal focus while a diverging lens always forms and upright image.
A. Both of these types of lenses have the ability to produce upright images.
Q3
Luminous intensity = illuminance × square radius
square radius = Luminous intensity/ illuminance
r² = 100/4
= 25
r = √25
= 5 m
Solution :
Let
kg
m/s
Let
and
are the speeds of the disk
and
after the collision.
So applying conservation of momentum in the y-direction,





Therefore, the disk 2 have greater velocity and hence more kinetic energy after the collision.
Now applying conservation of momentum in the x-direction,




m/s
So, 
= 4.33 m/s
Therefore, speed of the disk 2 after collision is 4.33 m/s