Answer:
b) True. the force of air drag on him is equal to his weight.
Explanation:
Let us propose the solution of the problem in order to analyze the given statements.
The problem must be solved with Newton's second law.
When he jumps off the plane
fr - w = ma
Where the friction force has some form of type.
fr = G v + H v²
Let's replace
(G v + H v²) - mg = m dv / dt
We can see that the friction force increases as the speed increases
At the equilibrium point
fr - w = 0
fr = mg
(G v + H v2) = mg
For low speeds the quadratic depended is not important, so we can reduce the equation to
G v = mg
v = mg / G
This is the terminal speed.
Now let's analyze the claims
a) False is g between the friction force constant
b) True.
c) False. It is equal to the weight
d) False. In the terminal speed the acceleration is zero
e) False. The friction force is equal to the weight
Answer:
Explanation:
The melting point of the solid is 80°C
Vapor point of the liquid is 140°C
What happens to particles of X when heated from 70°C to 85°C?
- Firstly, there would be a phase change from solid to liquid.
- Below the melting point, a substance will exist as a solid.
- With increase in thermal energy inputted by heat, as the temperature climbs above the melting point, it changes to the liquid.
- When the solid begins to heat up, the particles of X starts vibrating about their fixed point.
- At they melting point, they break lose and flow to form a liquid.
- The particles will have more kinetic energy.
It’s blurry the pic
But I think that is the second one
Been a while since i've done a problem like this so i might be wrong in the "work" aspect
your system starts with 1200J
you add 700J of heat-
add 700 to 1200
1200+700
and your system does 400J of work
since work is being done by the system, the energy is leaving the system hence you subtract
1900-400
the result is then 1500