Answer:
a. -369.36J
b. -123.9J
c. 9.52m
Explanation:
From the expression for kinetic energy
K. E=1/2mv^2
Since the mass is constant, but the velocity changes. Hence the change in kinetic energy is
K.E=1/2*19(3.6²-7.2²)
K.E= -369.36J
b. to determine the workdone by the force,we determine the distance moved.
But the acceleration is from
F=ma ,
a=f/m
a=-13/19
0.68m/s²
the distance moved is
s=v²/2a
s=3.6²/2*0.68
s=9.52m
Hence the work done is
W=force * distance
W=-13*9.52
W=-123.9J
d. the distance moved is
s=v²/2a
s=3.6²/2*0.68
s=9.52m
Answer:
Explanation:
This is basically asking you what the definition of Normal force is. Normal force is the force that pushes back against the weight of something that is sitting (or standing or lying) perpendicular to it. That's why, when you stand on a floor you don't crash through the floor OR go shooting up into space. The Normal force is equal but opposite to your weight. The floor exerts the normal force (pushing up and is positive) while your weight is opposing it (pushing down and is negative.) Perpendicular is the key word here, I believe.
Answer:
563712.04903 Pa
Explanation:
m = Mass of material = 3.3 kg
r = Radius of sphere = 1.25 m
v = Volume of balloon = 
M = Molar mass of helium = 
= Density of surrounding air = 
R = Gas constant = 8.314 J/mol K
T = Temperature = 345 K
Weight of balloon + Weight of helium = Weight of air displaced
Mass of helium is 6.4356 kg
Moles of helium
Ideal gas law
The absolute pressure of the Helium gas is 563712.04903 Pa
Explanation:
Water (H2O) as a polar covalent molecule has its arrangement of oxygen and hydrogen atoms where one end (hydrogen) has a partially positive charge while the other side (oxygen) had a partially negative charge.
It is also capable of forming hydrogen bonds with polar molecules. Each water molecule can form two hydrogen bonds involving their hydrogen atoms and two further hydrogen bonds using the hydrogen atoms attached to neighboring water molecules.
Answer:
Option D
Explanation:
The answer is option D or "the distance over which the force is applied." Since basic machinery is created to lessen the work for us humans reducing the strength of the force means that the distance which where the force is needed to be applied needs to be increased. Increasing the distance for the machine makes it all around more efficient. One of the most common examples of basic machinery is a rake. When using a rake, you do not need to apply as much force into it to make the rake efficient. If you increase the distance on where you are raking, then the amount you are raking increases, which means it's all-around efficiency increases.
Hope this helps.
