Answer:
17. h = l − l cos θ
18. 1.40 m
Explanation:
Let's call d the height of the triangle. We can then say:
h = l − d
Using trig, we can write d in terms of l and θ:
d = l cos θ
h = l − l cos θ
If l = 6 m and l cos θ = 40°:
h = 6 − 6 cos 40
h ≈ 1.40
Answer: frequency f = 2000 1/s (Hz)
Explanation: period T means time for one cycle and frequency f tells how many cycles there are in seconds. Unit of frequency is 1/s= Hz. Period T = 1/f and frequency f= 1/T.
E.g is T= 0.01 s then f= 1/ (0.01 s) = 100 Hz. And I'd frequency is 20 Hz,
T= 1/(20 Hz)= 0.05 s. So, if T = 0.005 s, f= 1/T
