Answer:
33 g.
Explanation:
Assuming no heat transfer can be possible except for heat exchange between water and steel, we can say that the heat lost by the knife, must be equal to the heat gained by the water.
As we have a limit for the maximum temperature of both elements (once reached a final thermal equilibrium), of 100ºC, which means that the maximum allowable change in temperature will be of 300º C for the knife, and of 80º C for the water.
Empirically , it has been showed that for a heat exchange process using only conduction, the heat needed to raise the temperature of a body, is proportional to the mass, being the proportionality constant a factor that depends on the material, called specific heat.
So, we can write the following equation:
cs*mk*Δtk = cw*mw*Δtw
Replacing by the givens of the question, we have:
0.11 cal/gºC * 80 g * 300ºC = 1 cal/gºC*mw*80ºC
Solving for mw = 2,640 cal / 80 cal/g =33 g.
Answer:
It doesn’t really relate
Explanation:
heavier load the parachute must be moving faster to match the downward force of the greater load
and approx terminal velocity when the parachute is open
velocity for Ping pong ball with parachute = 9m/s
velocity for Soccer ball with parachute = 15m/s
velocity for Golf ball with parachute =24m/s
velocity for Watermelon with parachute = 25m/s
so weight of an object doesn’t really realted how fast it falls with a parachute
To solve this problem we must consider the expressions of Stefan Boltzmann's law for which the rate of change of the radiation of energy H from a surface must be

Where
A = Surface area
e = Emissivity that characterizes the emitting properties of the surface
= Universal constant called the Stefan-Boltzmann constant 
T = Absolute temperature
The total heat loss would be then





Therefore the net rate of heat loss from the body by radiation is 155.29J
They are slowed down.
even air is a medium and will slow down waves (slightly) compared to a vacuum/ space
if the wave hits the medium at an angle it can be 'bent' (refracted) like light through a glass prism
Answer: It would be 75
Explanation: If your pushing on the floor at a rate of 5 for 15 seconds you would multiply the numbers and get 75