Answer:
see explanation
Step-by-step explanation:
Given that y varies inversely as x then the equation relating them is
y = 
← k is the constant of variation
To find k use the condition y = 5 , x = 21
k = yx = 5 × 21 = 105
y = 
← equation of variation
When x = 10, then
y = 
= 10.5
<span>7x - 5y =21
-7 -7
5y = 14
---- -----
5 5
y= 2.8
(4,2.8)</span>
Is there a picture that I can use to view where the angle of angle 7 is at?
Answer:
W1 = W2 = 50k Joules (assuming W1 and W2 have the same force constant, k)
W1 - W2 = 0
Step-by-step explanation:
Work done in stretching a spring is given by 1/2ke^2
Where, k is force constant and e is extension
e1 = 30cm - 20cm = 10cm
W1 = 1/2k(e1)^2 = 1/2×k×10^2 = 50k Joules
e2 = 40cm - 30cm = 10cm
W2 = 1/2k(e2)^2 = 1/2×k×10^2 = 50k Joules
W1 = W2 = 50k Joules provided W1 and W2 have equal force constant
Therefore, W1 - W2 = 0
