Answer:
-1786.5J
Explanation:
Temperature 1=T1=25°c
Temperature 2=T2=200°c
Pressure P1=1bar
Pressure P2=0.5bars
T=37°c+273=310k
Note number if moles=1
Recall work done =2.3026RTlogp2/P1
2.3026*8.314*310log(0.5/1)
-1786.5J
M = mass of aluminium = 1.11 kg
= specific heat of aluminium = 900
= initial temperature of aluminium = 78.3 c
m = mass of water = 0.210 kg
= specific heat of water = 4186
= initial temperature of water = 15 c
T = final equilibrium temperature = ?
using conservation of heat
Heat lost by aluminium = heat gained by water
M
(
- T) = m
(T -
)
(1.11) (900) (78.3 - T) = (0.210) (4186) (T - 15)
T = 48.7 c
Answer:
the force will decrease to 3/4 of its original value.
Explanation:
The initial electric force between the two charges is:

where
k is the Coulomb's constant
q is the magnitude of each charge
r is their separation
Later, half of one charge is transferred to the other charge; this means that one charge will have a charge of

while the other charge will be

So, the new force will be

So, the force will decrease to 3/4 of its original value.
Answer:

Explanation:
<u>Motion With Constant Acceleration
</u>
It's a type of motion in which the velocity of an object changes uniformly over time.
The equation that describes the change of velocities is:

Where:
a = acceleration
vo = initial speed
vf = final speed
t = time
Solving the equation for a:

The ball starts at rest (vo=0) and rolls down an inclined plane that makes it reach a speed of vf=7.5 m/s in t=3 seconds.
The acceleration is:

