Answer:
= 15 m/s
Explanation:
Considering right side(west) as positive x-axis and south as negative y-axis.
velocity of boat in still water 
velocity of stream 
now relative velocity of boat w.r.t. stream 
this velocity with which ac distance will be covered.
therefore magnitude of 
= 15 m/s
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Explanation:
Using Newtons second law on each block
F = m*a
Block 1

Block 2

Block 3

Solving Eq1,2,3 simultaneously
Divide 1 and 2

Put Eq 4 into Eq3

Put Eq 5 into Eq2 and solve for a

Substitute back in Eq2 and use Eq4 and solve for T2 & T1

<u>Answer:</u> The Young's modulus for the wire is 
<u>Explanation:</u>
Young's Modulus is defined as the ratio of stress acting on a substance to the amount of strain produced.
The equation representing Young's Modulus is:

where,
Y = Young's Modulus
F = force exerted by the weight = 
m = mass of the ball = 10 kg
g = acceleration due to gravity = 
l = length of wire = 2.6 m
A = area of cross section = 
r = radius of the wire =
(Conversion factor: 1 m = 1000 mm)
= change in length = 1.99 mm = 
Putting values in above equation, we get:

Hence, the Young's modulus for the wire is 
Theories have both an explanatory an a predictive function. True