Answer:
The specific heat capacity of the zinc metal measured in this experiment is 0.427 J/g.°C
Explanation:
From the experimental data, the water loses heat because its initial temperature is greater than the final temperature of the mixture. On the other hand, the zinc metal gains heat because its initial temperature is less than the final temperature of the mixture
Heat loss by water = Heat gain by zinc metal
m1C1(T1 - T3) = m2C2(T3 - T2)
m1 is mass of water = 55.4 g
C1 is specific heat capacity of water = 4.2 J/g.°C
m2 is mass of zinc metal = 23.4 g
C2 is specific heat capacity of zinc metal
T1 is the initial temperature of water = 99.61 °C
T2 is the initial temperature of zinc metal = 21.6 °C
T3 is the final temperature of the mixture = 96.4 °C
55.4×4.2(99.61 - 96.4) = 23.4×C2(96.4 - 21.6)
746.9028 = 1750.32C2
C2 = 746.9028/1750.32 = 0.427 J/g.°C
Answer:
The correct option is 'c':electron,proton,helium nucleus
Explanation:
The De-Broglie's wavelength of particle is given by
Thus we can see that wavelength is inversely related to mass of the particle since 'h' (Plank's constant) and velocity is same for all the particles
Thus we conclude that the the lightest particle will have the most wavelength
Electron being the lightest of the 3 particles will have the largest wavelength thus the correct option is 'c'. Since electron has the largest wavelength followed by proton and the least wavelength among the 3 is of helium.
<span>A student hears a police siren.
The arithmetic of the Doppler Effect shows that if the distance between
the source and observer is changing, then the observer hears a different
frequency compared to the frequency actually radiating from the source.
Thus the first four choices would cause the student to hear a different
frequency:
-- if the student walked toward the police car
-- if the student walked away from the police car
-- if the police car moved toward the student
-- if the police car moved away from the student
The last two choices wouldn't affect the frequency heard by the student,
since the perceived frequency of a sound doesn't depend on its intensity.
-- if the intensity of the siren increased
-- if the intensity of the siren decreased.</span>
How much gravitational potential energy does the block have
when it gets to the top of the ramp ?
(weight) x (height) = (15 N) x (0.2 m) = 3 Joules .
If there were no friction, you would only need to do 3 Joules of work
to lift the block from the bottom to the top.
But the question says you actually have to do 4 Joules of work
to get the job done.
Friction stole one of your Joules along the way.
Choice-4 is not the correct one.
Choice-1 is the correct one.
===========================
Notice that the mass of the block is NOT 15 kg , and you
don't have to worry about gravity to answer this question.
The formula for potential energy is (m)·(g)·(h) .
But (m·g) is just the WEIGHT, and the formula
is actually (weight)·(height).
The question GIVES us the weight of the block . . . 15 N .
So the potential energy at the top is just (15N)·(0.2m) = 3 Joules.
If you mean electromagnetic waves
Radio waves can be used well in radio signals
Infrared in remote controls
X rays for x-rays
Gamma rays in a nuclear power plant
Uv rays can cause cancer but they transmit vitamin D
