Answer:
Ft = 17.48°C
Explanation:
Ft is the final temperature. However, ice absorbs heat during two process of melting and cooling and as such, there is no loss of heat to or from the surrounding hence by conservation of energy.
Therefore,
Heat absorbed by water of 20g = heat rejected by water of 265g.
So; M(ice)[C(ice) [(ΔT) + LH(ice) + C(water)(ΔT)] = C(water) M(water) (ΔT)
So, 20[(2.108) [0 - (-20)] + 333.5 + 4.187(Ft - 0)]] = (285)(4.187) (25 - Ft)
To get;
7513 + 83.74 Ft = 29832.4 - 1193.3 Ft
So factorizing, we get;
83.74 Ft + 1193.3 Ft = 29832.4 - 7513
So; 1277.04 Ft = 22319.4
So; Ft = 22319.4/1277.04 = 17.48°C
(a) The skater covers a distance of S=50 m in a time of t=12.1 s, so its average speed is the ratio between the distance covered and the time taken:
(b) The initial speed of the skater is
while the final speed is
and the time taken to accelerate to this velocity is t=2 s, so the acceleration of the skater is given by
(c) The initial speed of the skater is
while the final speed is
since she comes to a stop. The distance covered is S=8 m, so we can use the following relationship to find the acceleration of the skater:
from which we find
where the negative sign means it is a deceleration.
Years of research have demonstrated that rats are intelligent creatures who experience pain and pleasure, care about one another, are able to read the emotions of others, and would assist other rats, even at their own expense.
<h3>Experiments:</h3>
In trials carried out at Brown University in the 1950s, rats were trained to press a lever for food, but they stopped pressing the lever when they noticed that with each press, a rat in an adjacent cage would scream in pain (after experiencing an electric shock).
Rats were trained to press a lever to lower a block that was hanging from a hoist by electric shocks administered by experimenters. A rat was subsequently hoisted into a harness by the experimenters, and according to their notes, "This animal normally shrieked and wriggled sufficiently while dangling, and if it did not, it was jabbed with a sharp pencil until it exhibited indications of discomfort." Even if it wasn't in danger of receiving a shock, a rat watching the scenario from the floor would pull a lever to lower the hapless rodent to safety.
Learn more about experiments on rats here:
brainly.com/question/13625715
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Answer:
Material's density
Explanation:
Seismic waves travel at different rates of speed based on a material's density. Hopefully, you understand that the Earth has three main layers: the crust, mantle, and core. Earthquake waves move faster through solids.
