<u>Answer</u>
8. 2 Hz
9. 0.5 seconds
10. 20 cm
<u>Explanation</u>
<u>Q 8</u>
Frequency is the number of oscillation in a unit time. It is the rate at which something repeats itself in a second.
In this case, the spring bob up and down 2 times per second.
∴ Frequency = 2 Hz
<u>Q 9</u>
Period is the time taken to complete one oscillation.
2 oscillations takes 1 second
1 oscillation = 1/2 seconds.
∴ Period = 0.5 seconds
<u>Q 10</u>
Amplitude is the the maximum displacement of the spring.
In this case the spring bob up 20 cm. This is it's displacement.
∴ Amplitude = 20 cm
Answer:
Astronomer Edmond Halley
Explanation:
The astronomical unit using the transit of venus
The underlying principle behind Halley's method is called parallax

EQUATOR IS THE LINE THAT DIVIDES EARTH INTO TWO HEMISPHERES .
The vector perpendicular to the plane of A = 3i+ 6j - 2k and B = 4i-j +3k is 16 i - 17 j - 27 k
Let r be the vector perpendicular to A and B,
r = A * B
A = 3i + 6j - 2k
B = 4i - j + 3k
a1 = 3
a2 = 6
a3 = - 2
b1 = 4
b2 = - 1
b3 = 3
a * b = ( a2 b3 - b2 a3 ) i + ( a3 b1 - b3 a1 ) j + ( a1 b2 - b1 a2 ) k
a * b = [ ( 6 * 3 ) - ( - 1 * - 2 ) ] i + [ ( - 2 * 4 ) - ( 3 * 3 ) ] j + [ ( 3 * - 1 ) - ( 4 * 6 ) ] k
a * b = 16 i - 17 j - 27 k
The perpendicular vector, r = 16 i - 17 j - 27 k
Therefore, the vector perpendicular to the plane of A = 3i + 6j - 2k and B = 4i - j + 3k is 16 i - 17 j - 27 k
To know more about perpendicular vectors
brainly.com/question/14384780
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