Impermeable is a substance that is water proofed e.g glass, aluminium e.t.c <span />
Kelvin is a base unit of temperature
scale from SI that defines as zero degree Kelvin (absolute zero). The absolute
zero is a hypothetical statement that all molecular movement stops because
there is no transient of energy for the molecules to move. When converting
temperature in degree Celsius to Kelvin, add 273. You are given 600K and you
are asked to find it in degrees Celsius.
T(K) = T(C) + 273
600 K = T(C) + 273
T(C) = 600 – 273
T(C) = 327 °C
<span>The answer is letter B.</span>
The ultimate energy source for wind comes from Earth's uneven heating on Earth's surface which can be caused mainly by the sun.
Answer:
(a) average velocity = 17.6 m/s
(b) when t = 0, v = 0
when t = 4, v = 19.2 m/s
when t = 8, v = 28.8 m/s
(c) after starting from rest, the car will be at rest again in 20 s
Explanation:
Given;
x(t)=bt²−ct³, substitute the given values and the equation will become;
x(t)=3t²−0.1t³
(a)average velocity = total distance / total time
total distance, x(t) = 3t²−0.1t³
x(8) = 3t²−0.1t³
X(8) = 3(8)² - 0.1(8)³
X(8) = 140.8 m
total time = 8 s
average velocity = 140.8 / 8
average velocity = 17.6 m/s
(b) instantaneous velocity = dx / dt
dx / dt = 6t - 0.3t²
when t = 0
v = 0
when t = 4 s
v = 6(4) - 0.3(4²) = 19.2 m/s
when t = 8 s
v = 6(8) - 0.3(8²) = 28.8 m/s
(c) the velocity is zero at dx / dt = 0
6t - 0.3t² = 0
t(6 - 0.3t) = 0
t = 0 or 6 - 0.3t = 0
t = 0 or 0.3t = 6
t = 0 or t = 6 / 0.3
t= 0 or t = 20 s
After starting from rest, the car will be at rest again in 20 s
