Answer:
the final temperature = 74.33°C
Explanation:
Using the expression Q = mcΔT for the heat transfer and the change in temperature .
Here ;
Q = heat transfer
m = mass of substance
c = specific heat
ΔT = the change in temperature
The heat Q required to change the phase of a sample mass m is:
Q = m
where;
is the latent heat of vaporization.
From the question ;
Let M represent the mass of the coffee that remains after evaporation is:
ΔT =
where;
m = 2.50 g
M = (240 - 2.50) g = 237.5 g
= 539 kcal/kg
c = 1.00kcal/kg. °C
ΔT =
ΔT = 5.67°C
The final temperature of the coffee is:
ΔT
where ;
= initial temperature = 80 °C
= (80 - 5.67)°C
= 74.33°C
Thus; the final temperature = 74.33°C
Answer:3
Explanation:
First ball is thrown with horizontal velocity while other ball is dropped from cliff such that both have zero vertical velocity. So both balls have to cover a distance equal to the height of cliff with same initial velocity.
time taken is given by
where h=height of cliff
g=acceleration due to gravity
horizontal velocity to first ball will make the ball to travel more horizontal distance as compared to second ball.
Option 3 is correct
Answer:
750cm³
Explanation:
volume = length × width × height
15 × 10 × 5 = 750
750cm³
Answer:
The distance is, y = 489.5 [m/s]
Explanation:
To solve this problem we can use the following equation of kinematics.
where:
Vf = final velocity = 98 [m/s]
Vi = initial velocity = 0
g = gravity acceleration = 9.81 [m/s^2]
y = distance [m]
(98^2) = 0 + (2*9.81*y)
Note: the positive sign of the equation means that the acceleration of gravity acts in the direction of the movement of the object.
9604 = 19.62*y
y = 489.5 [m/s]
The current initially through the fingers is : 1.5 * 10⁻⁵ amp
The current when the resistance between them drops is : 3 * 10⁻⁵ amp
<u>Given data : </u>
Voltage ( V ) = 6 V
Initial resistance ( r ) = 400,000 ohms
Final resistance ( R ) = 200,000 ohms
<h3>Determine The Current </h3>
A) initially through fingers
I = V / r
= 6 V / 400,000
= 1.5 * 10⁻⁵ amp
B) when the resistance between them drops
I = V / R
= 6 V / 200000
= 3 * 10⁻⁵ amp
Hence we can conclude that The current initially through the fingers is : 1.5 * 10⁻⁵ amp and The current when the resistance between them drops is : 3 * 10⁻⁵ amp
Learn more about current calculation : brainly.com/question/25922783