Answer:
c Like/same signs
Explanation:
A repelling force occurs between two or more charged objects with the charges are of like or same sign.
- According to Coulombs law, like charges repel on another, unlike charges attracts on another.
- If a positive charge comes into the vicinity of another positive charge, there will be repulsion.
- When oppositely charge species are brought near each other, there is an attraction.
Therefore, repulsion occurs when like charges are brought close to each other.
Answer:
ambulance speed is 30.38 m/s
Explanation:
given data
hear frequency = 510 Hz
pass frequency = 427 Hz
speed of sound = 343 m/s
to find out
ambulance speed
solution
we consider here ambulance speed is v
so when we hear frequency velocity equation will be
510 = 343f / ( 343 - v ) ...........................1
and when ambulance pass velocity equation will be
427 = 343f / ( 343 + v ) ...........................2
so from equation 1 and equation 2
= 510 / 427
= 510 / 427
solve it we get
v = 30.38 m/s
so ambulance speed is 30.38 m/s
Use this kinematics equation:
Vf = Vi + aΔt
Vf is the final velocity, Vi is the initial velocity, a is the acceleration, and Δt is the elapsed time.
Assign northward velocity/acceleration as positive and southward as negative. Given values:
Vi = 100km/h = 27.8m/s
a = -4m/s²
Δt = 6s
Plug in the values and solve for Vf:
Vf = 27.8 - 4(6)
Vf = 3.8m/s north
Answer:
Temperature when sound wave with wavelength 0.47m has frequency 741 hz is 188 degrees Centigrade.
Step-by-Step Explanation:
Given:
Speed of sound at 0 degrees centigrade = 235 ms
frequency = f = 741 hz
wavelength = w = 0.47m
speed of sound wave = wavelength * frequency = 741 * 0.47 = 348.27 m/s
Using the formula for speed of sound at a specific temperature:
Speed of sound at T degrees Centigrade = Speed of sound at 0 degrees + 0.6 * T
When speed of sound is 348 m/s, the temperature is given by:
348 = 235 + 0.6(T)
T = (348-235)/0.6
T = 188 degrees Centigrade
Answer:
Initial velocity = 39.2m/s
Maximum height is 78.4m
Explanation:
Given
Solving (a): Initial Velocity
Using first law of motion:
Where
<em /><em> [g represents acceleration due to gravity]</em>
Substitute these value in the above formula:
Take g as 9.8m/s²
<em>Hence, initial velocity = 39.2m/s</em>
Solving (b): Maximum Height
This will be solved using second equation of motion
This becomes
Substitute values for u, t and g
<em>Hence, the maximum height is 78.4m</em>