Answer:
A.100J
Explanation:
Given parameters:
Force on car = 20N
Distance = 5m
Unknown:
Work done = ?
Solution:
Work done is the product of force and distance;
Work done = force x distance;
Insert given parameters and solve;
Work done = 20 x 5 = 100J
Hi there!
We can begin by calculating the time taken to reach its highest point (when the vertical velocity = 0).
Remember to break the velocity into its vertical and horizontal components.
Thus:
0 = vi - at
0 = 16sin(33°) - 9.8(t)
9.8t = 16sin(33°)
t = .889 sec
Find the max height by plugging this time into the equation:
Δd = vit + 1/2at²
Δd = (16sin(33°))(.889) + 1/2(-9.8)(.889)²
Solve:
Δd = 7.747 - 3.873 = 3.8744 m
The Kelvin scale has no negatives on it.
Zero Kelvin is 'Absolute Zero', and nothing can get colder than that.
The refractive index for glycerine is

, while for air it is

.
When the light travels from a medium with greater refractive index to a medium with lower refractive index, there is a critical angle over which there is no refraction, but all the light is reflected. This critical angle is given by:

where n1 and n2 are the refractive indices of the two mediums. If we susbtitute the refractive index of glycerine and air in the formula, we find the critical angle for this case:
Answer:
915 Hz
Explanation:
The observed frequency from a sound source is given as
f₀ = f [(v + v₀)/(v+vₛ)]
where
f₀ = observed frequency of the sound by the observer = ?
f = actual frequency of the sound wave = 983 Hz
v = actual velocity of the sound waves = 343 m/s
vₛ = velocity of the source of the sound waves = 55.9 m/s
v₀ = velocity of the observer = 28.4 m/s
f₀ = 983 [(343+28.4)/(343+55.9)]
f₀ = 915.2 Hz = 915 Hz