Answer:
Vf = 69.56 cm/s
Explanation:
In order to find the final speed of the ramp, we will use the equations of motion. First we use second equation of motion to find out the acceleration of marble:
s = Vi t + (1/2)at²
where,
s = distance traveled = 160 cm
Vi = Initial Speed = 0 cm/s (since, marble starts from rest)
t = time interval = 4.6 s
a = acceleration = ?
Therefore,
160 cm = (0 cm/s)(4.6 s) + (1/2)(a)(4.6 s)²
a = (320 cm)/(4.6 s)²
a = 15.12 cm/s²
Now, we use first equation of motion:
Vf = Vi + at
Vf = 0 cm/s + (15.12 cm/s²)(4.6 s)
<u>Vf = 69.56 cm/s</u>
Answer: A
Explanation: We know that f=p*n
f=50*300=15000 Hz = 15kHz.
Have a great day! <3
Answer:
a. when the acceleration of the objects become negative
Given : Time taken to reach the maximum height t=3 s a=−g=−10m/s
2
The initial velocity of the ball can be calculated by,
Using v=u+at
∴ 0=u−10×3 ⟹u=30 m/s
Using S=ut+
2
1
at
2
∴ S=30×3+
2
1
×(−10)×3
2
=45m
