Answer:
4 seconds
Explanation:
Given:
v₀ = 0 m/s
v = 20 m/s
a = 5 m/s²
Find: t
v = at + v₀
20 m/s = (5 m/s²) t + 0 m/s
t = 4 s
Answer:
d) It will be cut to a fourth of the original force.
Explanation:
The magnitude of the electrostatic force between the charged objects is

where
k is the Coulomb's constant
q1 and q2 are the charges of the two objects
r is the separation between the two objects
In this problem, the initial distance is doubled, so
r' = 2r
Therefore, the new electrostatic force will be

So, the force will be cut to 1/4 of the original value.
Answer:
f = 3.1 kHz
Explanation:
given,
length of human canal =2.8 cm = 0.028 m
speed of sound = 343 m/s
fundamental frequency = ?
The fundamental frequency of a tube with one open end and one closed end is,



f = 3062.5 Hz
f = 3.1 kHz
hence, the fundamental frequency is equal to f = 3.1 kHz