The answer to that would be that
they require so its mandatory for mechanical waves to travel through a medium
Answer:
Explanation:
Given
Minute hand length =16 cm
Time at a quarter after the hour to half past i.e. 1 hr 45 min
Angle covered by minute hand in 1 hr is 360 and in 45 minutes 270


(c)For the next half hour
Effectively it has covered 2 revolution and a quarter

angle turned 
(f)Hour after that
After an hour it again comes back to its original position thus displacement is same =25.136
Angle turned will also be same i.e. 
Answer:
A mirror that has a reflecting surface that is recessed inward is called concave mirror
Answer:
a = 5.05 x 10¹⁴ m/s²
Explanation:
Consider the motion along the horizontal direction
= velocity along the horizontal direction = 3.0 x 10⁶ m/s
t = time of travel
X = horizontal distance traveled = 11 cm = 0.11 m
Time of travel can be given as

inserting the values
t = 0.11/(3.0 x 10⁶)
t = 3.67 x 10⁻⁸ sec
Consider the motion along the vertical direction
Y = vertical distance traveled = 34 cm = 0.34 m
a = acceleration = ?
t = time of travel = 3.67 x 10⁻⁸ sec
= initial velocity along the vertical direction = 0 m/s
Using the kinematics equation
Y =
t + (0.5) a t²
0.34 = (0) (3.67 x 10⁻⁸) + (0.5) a (3.67 x 10⁻⁸)²
a = 5.05 x 10¹⁴ m/s²
Why can you get a shock if you touch a metal doorknob after walking across a wool carpet is because you have gained neutrons; the doorknob has fewer electrons. This is further explained below.
<h3>What are electrons?</h3>
Electrons can be defined as a stable subatomic particles with a negative electrical charge that is found in all atoms and serves as the major carrier of electricity in solids.
In conclusion, You have an unbalanced charge, while the doorknob is neutral. you have gained neutrons; the doorknob has fewer electrons.
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