Answer:
An object which moves in the positive direction has a positive velocity. If the object is slowing down then its acceleration vector is directed in the opposite direction as its motion (in this case, a negative acceleration).
Explanation:
If bonds are broken, the energy is released, and if bonds are formed, energy is absorbed. During conversions from chemical energy to thermal energy, the energy stored in the chemical bonds are released and this energy causes surrounding molecules to move faster thus increasing the thermal energy of a substance.
Explanation:
(a)
Critical angle is the angle at the angle of refraction is 90°. After the critical angle, no refraction takes place.
Using Snell's law as:
Where,
is the angle of incidence
is the angle of refraction = 90°
is the refractive index of the refraction medium
is the refractive index of the incidence medium
Thus,
The formula for the calculation of critical angle is:
Where,
is the critical angle
(b)
No it cannot occur. It only occur when the light ray bends away from the normal which means that when it travels from denser to rarer medium.
Atmospheric pressure is caused by the weight of the atmosphere pushing down on itself and on the surface below it.
Pressure is defined as the force acting on an object divided by the area upon witch the force is acting.
Answer:
50%
Explanation:
Humidity is the amount water vapor present in the atmosphere.
Relative humidity is defined as the ratio of partial water vapor present in air to the actual water vapor at a particular temperature. It is expressed in percentage and the higher the percentage RH, the more the saturated water vapor present in the atmosphere and vice versa.
It is expressed mathematically as shown;
RH = actual water vapor in air/saturated water vapor × 100%
If the actual water vapor in the air was 4 grams per cubic meter and the air's capacity to hold water vapor was 8 grams per cubic meter
Actual water vapor = 4g/cm³
Air's water capacity (saturated water vapor) = 8g/cm³
RH = 4/8×100
RH = 50%
