Answer:
Large shovels
Explanation:
If you are wondering specifically when to use long handled shovels, they are better for tree planting and other hole-digging. Long shovel handles can reach deep into a hole. And you'll get better leverage, which is easier on your back. The lighter the shovel, the easier time you will have digging.
Answer:
The net force is zero, if there is not external forces. The net force if the body is accelerating will be the product of the mass by the acceleration.
Explanation:
If the box does not accelerate, there are two possible options, either the box moves at constant velocity or does not receive any external force to alter its balance.
Newton's Second Law, also known as the Fundamental Law of dynamics, determines a proportional relationship between Force and variation of the amount of motion or linear moment of a body. In other words, The Force is directly proportional to the mass and acceleration of a body.
If there are forces acting on the body and these forces are not in balance the body will move with a resulting force equal to the product of mass by acceleration.
Sitting = no movement
KE=0
To solve this problem we will apply Henry's law. This law states that at a constant temperature, the amount of gas dissolved in a liquid is directly proportional to the partial pressure exerted by that gas on the liquid. Mathematically it is formulated as follows:
Here
is the partial pressure of the gas.
is the concentration of the gas (solubility).
is Henry's constant, which depends on the nature of the gas, the temperature and the liquid.
At the same time we know the the concentration can be defined as the relation between the number of moles and volume, then
Then we have that the relation can be written now as,
Now the fraction of Oxygen in that quantity is 0.21, then
Mass of oxygen
Therefore the mass of oxygen is 30.1324mg