I don't really now a answer to the first one but this answer is for the second one: They provide a standardized system of classification for a language barrier.
Answer:
= 128.3 J / kg ° C
Explanation:
In this exercise we will use that the expression for heat is
Q = m ΔT
As they indicate that there are no losses with the medium, the heat transferred by the tungsten is equal to the heat absorbed by the water plus the calorimeter
Q assigned = QAbsorbed
Q hot = Q cold + Q calorimeter
The mass of tungsten (m₁ = 69.12 10⁻³ kg) with an initial temperature (T₁ = 98.93°C),
The mass of water (m₂ = 85.45 10⁻³ kg) at a temperature (T₂ = 23.82°C),
a calorimeter constant (C = 1.56 J/ °C)
m₁ (T₁ - ) = (m₂ + C) ( - T₂)
= (m₂ ce2 + C) (-T₀) / (m₁ (T₁-)
= (85.45 10-3 4186 + 1.56) (25.63 - 23.82) / (69.12 10-3 (98.93 - 25.63))
= (357.69 + 1.56) 1.81 / (69.12 10-3 73.3)
= 650.24 / 5.0665
= 128.3 J / kg ° C
Note that
The specific heat of water is 4.184 J/(g -C)
Let x = the final equilibrium temperature.
Heat loss by the copper is
(155 g)*(0.385 J/(g -C))*(168 - x C) = 59.675(168 -x) J
Heat gain by the water is
(250 g)*(4.184 J/(g-C))*(x - 20.9 C) = 1046(x - 20.9) J
Because there is no heat loss to the surroundings, therefore
59.675(168 - x) = 1046(x - 20.9)
168 - x = 17.5283(x - 20.9)
18.5283x = 534.3415
x = 28.84 °C
Answer: 28.8 °°C nearest tenth)
Answer:
1) 1.08 m/s^2
Explanation:
Acceleration is equal to the change in velocity divided by the time taken:
where
v is the final velocity
u is the initial velocity
is the time taken
In this problem, we have:
- initial velocity: u = 0 (you start from rest)
- final velocity: v = 5.4 m/s
- time taken:
Therefore, the acceleration is
2) -0.54 m/s^2
We can calculate the acceleration to slow down using the same formula as before, but this time the data are as follows:
- initial velocity : u = 5.4 m/s
- final velocity : v = 0 (you come to a stop)
- time taken :
using the same formula, we find
And the negative sign means it is a deceleration.
Answer:
Explanation:
Since the compass uses a magnetic field, if anything else magnetic is near it, the compass will start acting up. Making it unreliable so keep magnets away!