"Constant velocity" means zero acceleration, which means zero net force. So there must be100N pulling on the crate to cancel the 100N of friction force.
General expression is;
Pressure = Force/Area
In which,
Pressure = Required pressure + Atmospheric pressure = (1.2*10^5) + (101325) = 221325 Pa = 221325 N/m^2
Area = πD^2/4 = π*0.035^2/4 = 9.621*10^-4 m^2
Therefore,
Force, F = Pressure*Area = 221325*9.621*10^-4 = 212.94 N
Prior to determining the
experimental design, a scientist typically forms a hypothesis. The answer is
letter B. this is to prepare the scientist, the possible outcome of their
research before the experimental design whether they are wrong or not.
<h2>Right answer: Sea breeze </h2>
The sea breeze is formed because during the day the surface of the land on the coast tends to warm up before and more than the surface of the sea. This difference in temperature between these two air masses means that on a sunny day the land warms up much more than the ocean causing a small area of low pressure.
Then, the air rises as the land warms it and the colder air located on the surface of the sea forms a high pressure zone that makes this air mass tend to occupy the space left by the warmer air that has ascended on the coast. Therefore, the mass of air of a high pressure on the ocean always tends to move towards the zone of low pressure located on the coast.
It is important to note that the <u>sea breeze blows perpendicularly to the coast</u> and that the best breezes are formed in the spring and summer seasons because during the spring the water temperature is still cold and during the summer the sun produces high temperatures over the land in the coast.
<h2>So, <u>
the greater the temperature contrast </u>
between the land and the sea, <u>
the greater the force of the wind generated</u>
.</h2>
Acceleration is the rate of change of velocity, so can be calculated by:
a = v2 - v1 / t where v2 and v1 are the final and initial velocities of the object respectively and t is the time taken. Therefore the acceleration is:
a = 30 m/s - 20 m/s / 2.0 s = 10 m/s / 2.0 s = 5 m/(s^2)
Hope this helps!
