Gamma radiation could be used to sterilize plastic petri plates in a plastic wrapper.
Answer: Option E
<u>Explanation:
</u>
It is known that radioactive radiations have greater ionizing powers compared to other electromagnetic radiations. Among the radioactive radiations, gamma rays are the most ionizing radiation.
So they are widely used in sterilizing process. As the penetration power of gamma is more compared to alpha and beta, in order to kill microorganisms gamma radiations are used.
When plastic petri plates wrapped with plastic are bombarded or sterilizing with gamma rays, the rays will ionise the micro-organism. Thus mutilating their DNA and preventing their reproduction.
components of the speed of the coin is given as




now the time taken by the coin to reach the plate is given by



now in order to find the height



so it is placed at 1.52 m height
Mass have no effect for the projectile motion and u want to know the height "h"
first,
find the vertical and horizontal components of velocity
vertical component of velocity = 12 sin 61
horizontal component of velocity = 12 cos 61
now for the vertical motion ;
S = ut + (1/2) at^2
where
s = h
u = initial vertical component of velocity
t = 0.473 s
a = gravitational deceleration (-g) = -9.8 m/s^2
h=[12×sin 610×0.473]+[−9.8×(0.473)2]
u can simplify this and u will get the answer
h=.5Gt2
H=1.09m
A. To find work we need to know F and S; to find power we need to know F and V
Answer:
F = 4000 N
Explanation:
given,
mass of rocket (M)= 5000 Kg
10 Kg gas burns at speed (m)= 4000 m/s
time = 10 s
average force = ?
at the end the rocket is at rest
by conservation of momentum
M v + m v' = 0
5000 x v - 10 x 4000 = 0
5000 v = 40000
v = 8 m/s
speed of rocket = 8 m/s
now,
we know
change in momentum = F x Δ t


F = 4000 N
Hence, the average force applied to the rocket is equal to F = 4000 N