The suspended ash made for some some spectacular sunsets! Sulfuric acid was spread worldwide, increasing acidity of rain. Ash deflected energy from the sun, causing a slight drop on global temps for a few years.
*heat transfer energy, As it always flow from higher temperature to lower temperature till it reach the thermal equilibrium.
example: -friction.
- collisions.
- the hot cup which's hotter than your hand✋will transfer heat in your hand. and a cold piece of ice which's colder than your hand to causing the heat transfer out of your hand .
*temperature ️ depends on the move of particle and we have a different shape of motion like:
translational motion.
rotational motion.
vibrational motion.
when the temperature:
increases it has more kinetic energy and faster moving particles and the object expanded which known as (thermal expansion).
decreases it has less kinetic energy and slower moving particles.
As kinetic energy is 1/2 mV².
example: -the mercury in thermometers.
*Absolute zero :
The theoretical temperature at which substances possess no thermal energy, equal to 0 K, −273.15°C, or −459.67°F.
*specific heat "c" :
is essentially a measure of how thermally insensitive a substance is to the addition of energy.
c=Q/m∆T
where Q is energy .
note water has a higher specific heat, and lower temperature.
*conduction <em><u>example</u></em> When the stove is turned on, the skillet becomes very hot due to the conduction of heat from the burner to the skillet.
Answer: The changing magnetic field caused by the material's motion induces a current in the coil of wire proportional to the change in field. If a 0 is represented, the magnetic field does not change between the two domains of a bit, so no current is induced as the magnetic material passes the coil.
From tables, the speed of sound at 0°C is approximately
V₁ = 331 m/s (in air)
V₃ = 5130 m/s (in iron)
Distance traveled is
d = 100 km = 10⁵ m
Time required to travel in air is
t₁ = d/V₁ = 10⁵/331 = 302.12 s
Time required to travel in iron is
t₂ = d/V₂ = 10⁵/5130 = 19.49 s
The difference in time is
302.12 - 19.49 = 282.63 s
Answer: 283 s (nearest second)
Answer:
a) x(t) = 10t + (2/3)*t^3
b) x*(0.1875) = 10.18 m
Explanation:
Note: The position of the horse is x = 2m. There is a typing error in the question. Otherwise, The solution to cubic equation holds a negative value of time t.
Given:
- v(t) = 10 + 2*t^2 (radar gun)
- x*(t) = 10 + 5t^2 + 3t^3 (our coordinate)
Find:
-The position x of horse as a function of time t in radar system.
-The position of the horse at x = 2m in our coordinate system
Solution:
- The position of horse according to radar gun:
v(t) = dx / dt = 10 + 2*t^2
- Separate variables:
dx = (10 + 2*t^2).dt
- Integrate over interval x = 0 @ t= 0
x(t) = 10t + (2/3)*t^3
- time @ x = 2 :
2 = 10t + (2/3)*t^3
0 = 10t + (2/3)*t^3 + 2
- solve for t:
t = 0.1875 s
- Evaluate x* at t = 0.1875 s
x*(0.1875) = 10 + 5(0.1875)^2 + 3(0.1875)^3
x*(0.1875) = 10.18 m