Answer:
option (B)
Explanation:
Young's modulus is defined as the ratio of longitudinal stress to the longitudinal strain.
Its unit is N/m².
The formula for the Young's modulus is given by

where, F is the force applied on a rod, L is the initial length of the rod, ΔL is the change in length of the rod as the force is applied, A is the area of crossection of the rod.
It is the property of material of solid. So, when the 10 wires are co joined together to form a new wire of length 10 L, the material remains same so the young' modulus remains same.
Answer:
The fundamental wavelength of the vibrating string is 1.7 m.
Explanation:
We have,
Velocity of wave on a guitar string is 344 m/s
Length of the guitar string is 85 cm or 0.85 m
It is required to find the fundamental wavelength of the vibrating string. The fundamental frequency on the string is given by :

Now fundamental wavelength is :

So, the fundamental wavelength of the vibrating string is 1.7 m.
In Newton's Cradle experiment we know that all cradles of same mass and identical to each other
Now we know that when two identical objects collide elastically then they interchange their velocity
So here we have same illustration
When Newton pulls up a cradle and release it will move hit another cradle which is at rest
Due to elastic collision between them first cradle comes to rest and another cradle will move ahead with same speed this process remains the same and one by one all cradle hit another.
So at the last the cradle at the end will move off with the same speed as the first cradle will hit with the speed.
So in this experiment the cradle at the last end will move off at same distance away from the right end as that of left end we pull the cradle.
So here we can say that in horizontal direction when all cradles are colliding each other there is no external force on the system so momentum is conserved and they all will move off with same speed and hence we observe the above condition.
Answer:
v = 478.26 km/h
Explanation:
The question is "find in km.h the speed of a tiger that runs 550 km in 69min"
Distance, d = 550 km
Time, t = 69 min = 1.15 h
We need to find the speed of the tiger. The speed of an object is equal to the total distance covered divided by time taken. So,

So, the speed of the tiger is 478.26 km/h.
Answer:
Thus, the time for the first lamp is 44 minutes.
Explanation:
Power of first lamp, P' = 1000 W
Power of second lamp, P'' = 4400 W
time for second lamp, t'' = 10 minutes
Let the time for first lamp is t'.
As the energy is same, so,
P' x t' = P'' x t''
1000 x t' = 4400 x 10
t' = 44 minutes