Answer:
67 kPa
Explanation:
Given that,
Initial volume, V₁ = 25 cm³
Initial pressure, P₁ = 100 kPa
Final volume, V₂ = 15 cm³
We need to find the change in pressure of the gas. The relation between the volume and pressure of a gas is given by :
or
= 167 kPa
The change in pressure,
= P₂ - P₁
= 167 kPa - 100 kPa
= 67 kPa
Hence, the correct option is (a).
To Find :
Which element accumulates in the environment due to the use of fertilizers.
Solution :
Most of the fertilizers used in daily practice are nitrogen fertilizers .
When soil became waterlogged, soil organisms take the oxygen they need from nitrates, leaving the nitrogen in a gaseous form which escapes into the air.
Also, nitrogen is very stable and did not participate in most of the reactions.
So, nitrogen is accumulates in the environment .
Therefore, option C. is correct.
Answer:
This equation is based on twin paradox - a phenomena where one of the twin travels to space at a speed close to speed of light and the other remains on earth. the twin from the space on return discovers that the one on earth age faster.
Solution:
= 10 years
v = 0.8c
c = speed of light in vacuum
The problem can be solved by time dilation equation:
(1)
where,
t = time observed from a different inertial frame
Now, using eqn (1), we get:
t = 16.67 years
The age of the twin on spaceship according to the one on earth = 25+16.67 =41.66 years
Answer:
T = 19.75 N
Explanation:
given,
mass of ball = 0.25 Kg
radius = 0.5 m
frequency = 2 s⁻¹
tension in the string = ?
angular velocity
ω = 2 π f
ω = 2 π x 2
ω = 12.57 rad/s
tension on the string is equal to the centripetal force
T = m ω² r
T = 0.25 x 12.57² x 0.5
T = 19.75 N
Tension in the string is equal to T = 19.75 N
Answer: 
Explanation:
According to Newton's law of universal gravitation:
Where:
is the module of the force exerted between both bodies
is the universal gravitation constant.
and 
are the masses of both bodies.
is the distance between both bodies
In this case we have two situations:
1) Two bags with masses 
and mutually exerting a gravitational attraction 
on each other:
(1)
(2)
(3)
2) Two bags with masses 
and 
mutually exerting a gravitational attraction 
on each other (assuming the distance between both bags is the same as situation 1):
(4)
(5)
(6)
Now, if we isolate 
from (3):
(7)
Substituting found in (7) in (6):
(8)
(9)
Simplifying, we finally get the expression for in terms of
:
