Answer:
The average kinetic energy of the molecules increases
Explanation:
The temperature of a substance is proportional to the average kinetic energy of the particles in the substance.
In fact, for an ideal gas for instance, there is the following relationship:
where
KE is the average kinetic energy of the particles
k is the Boltzmann's constant
T is the absolute temperature of the gas
When we heat a substance (such as the flask of water in this problem), we are giving thermal energy to the particles of the substance; therefore, these particles will move faster on average, so their kinetic energy will increase (and the temperature of the substance will increase as well).
I have read that it is enough energy to power the needs of civilization for an entire year.
I'll assume that the chair has four legs.
Since the chair weights 3.7 kg by itself, it will weigh (79+3.7)=82.7 kg with the person sitting on it. And each of the chair's legs will take about (82.7/4)=20.675 kg.
Each leg touches the floor in a circle with 1.3cm diameter. The area of that circle is about (3.14*(1.3/2)^2)=1.327 cm^2.
Pressure is measured by force per area. So, the pressure from each leg is about 20.675kg / 1.327cm^2. That simplifies to 15.58 kg/cm^2.
Answer:
330 m/s
Explanation:
The sound wave has to travel TO the cliff AND back = 2 * 49.5 = 99 m
magnitude of velocity = distance / time = 99m / .3 s = 330 m/s
Answer:
Answer:
4 ms
Explanation:
initial velocity, u = 75 m/s
final velocity, v = 0
distance, s = 15 cm = 0.15 m
Let the acceleration is a and the time taken is t.
Use third equation of motion
v² = u² + 2 a s
0 = 75 x 75 - 2 a x 0.15
a = - 18750 m/s^2
Use first equation of motion
v = u + at
0 = 75 - 18750 x t
t = 4 x 10^-3 s
t = 4 ms
thus, the time taken is 4 ms.
Explanation:
