4. Intermediate conductivity and a low melting point.
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Wavelength - the distance from one wave crest or trough to another wave crest or trough. Amplitude - the distance from the median point or "middle" of the wave straight up to a crest (a maximum) or straight down to a trough (or minimum), which is the peak amplitude; or the distance from a trough straight up to a crest, or a crest straight down to a trough, called peak-to-peak amplitude.
Answer:
the angular acceleration of the car is 1.5 rad/s²
Explanation:
Given;
initial angular velocity,
= 10 rad/s
final angular velocity,
= 25 rad/s
time of motion, t = 10 s
The angular acceleration of the car is calculated as follows;

Therefore, the angular acceleration of the car is 1.5 rad/s²
Answer:
The air resistance on the skydiver is 68.6 N
Explanation:
When the skydiver is falling down, there are two forces acting on him:
- The force of gravity, of magnitude
, in the downward direction (where m is the mass of the skydiver and g is the acceleration due to gravity)
- The air resistance,
, in the upward direction
So the net force on the skydiver is:

where
m = 7.0 kg is the mass

According to Newton's second law of motion, the net force on a body is equal to the product between its mass and its acceleration (a):

In this problem, however, the skydiver is moving with constant velocity, so his acceleration is zero:

Therefore the net force is zero:

And so, we have:

And so we can find the magnitude of the air resistance, which is equal to the force of gravity:

Answer:
Calcium sulphide
Explanation:
If we look at the compound, we will discover that it is an ionic compound. The compound is comprised of Ca^2+ and S^2-.
The cation Ca^2+ is the calcium ion while the anion S^2- is the sulphide ion hence the compound is rightly named calcium sulphide.