Answer:
20cm
Explanation:
A convex lens has a positive focal length and the object placed in front of it produce both virtual and real image <em>(image distance can be negative or positive depending on the nature of the image</em>).
According to the lens equation
where;
f is the focal length of the lens
u is the object distance
v is the image distance
If the magnification is - 0.6
mag = v/u = -0.5
v = -0.5u
since v = 10cm
10 = -0.5u
u = -10/0.5
u =-20 cm
Substitute u = -20cm ( due to negative magnification)and v = 10cm into the lens formula to get the focal length f
Hence the focal length of the convex lens is 20cm
The answer is :78 I think
The period of the transverse wave from what we have here is 0.5
<h3>How to find the period of the transverse wave</h3>
The period of a wave can be defined as the time that it would take for the wave to complete one complete vibrational cycle.
The formula with which to get the period is
w = 4π
where w = 4 x 22/7
2π/T = 4π
6.2857/T = 12.57
From here we would have to cross multiply
6.2857 = 12.57T
divide through by 12.57
6.2857/12.57 = T
0.500 = T
Hence we can conclude that the value of T that can determine the period based on the question is 0.500.
Read more on transverse wave here
brainly.com/question/2516098
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Answer:
(a) - 42700 m/s
(b) - 6.8 x 10^-4 m/s^2
Explanation:
initial velocity of star, u = 20.7 km/s
Final velocity of star, v = - 22 km/s
time, t = 1.99 years
Convert velocities into m/s and time into second
So, u = 20700 m / s
v = - 22000 m/s
t = 1.99 x 365.25 x 24 x 3600 = 62799624 second
(a) Change in planet's velocity = final velocity - initial velocity
= - 22000 - 20700 = - 42700 m/s
(b) Accelerate is defined as the rate of change of velocity.
Acceleration = change in velocity / time
= ( - 42700 ) / (62799624) = - 6.8 x 10^-4 m/s^2
