To determine the period of a wave you need not utilize the value for the wave speed.
The formula for the period is T= 1/f
T stands for period/time while f is for frequency. Substitute the value for the frequency which is 60 Hz. That would give you:
T= 1/60 Hz
convert Hz to cycles per second to extract the unit of time (s).
60 Hz x 1/s/1 Hz= 60/s
To continue the computation:
T=1/60/s that will give you a T= 0.017 s or 17 ms.
Explanation:
hope you understood fella
I believe the answer is D
Hope this helps :)
M= 4kg
v= ?
momentum = Mv
so
12kgms-¹ = 4kg×v
v= 12÷4 = 3ms-¹
So we want to know what is the distance d of the object from the lens if the height of the object is h=6 cm, focal length of the lens is f=5 cm and the distance d=15 cm is the distance of the object from the lens. From the formula for the convex lens 1/f=(1/D + 1/d) where D is the distance of the image from the lens we can get D after solving for D: 1/D=(1/f) - (1/d),
1/D=(1/5)-(1/15)=0.2-0,06667=0.13333 so f=1/0.13333=7.500187 cm. Rounded to the nearest hundredth D=7.50 cm. That is very close to 7.69 cm so the correct answer is the third one.
