<span>The metric
system is the oldest name for the international system of units. The answer is <u>a.
True. </u>SI unit or the international systems of units are based on seven
basic units; the meter, kilogram, second, ampere, Kelvin, candela and mole. All
of these basic units are divided into multiples by a power of ten. For example
in meters, 1 meter is equal to: 1000 millimeter, 100 centimeter, 10 decimeter,
0.1 decameter, 0.01 hectometer, 0.001 kilometer and so on and so forth.</span>
Alice and Jim will put 2,400 Joules of energy into the situation,
and 1,800 Joules of energy will come out in a useful form.
The efficiency of the whole process will be
1800 J / 2400 J = 3/4 or 75% .
Answer:
0.70 s
Explanation:
Potential energy = kinetic energy + rotational energy
mgh = ½ mv² + ½ Iω²
For a thin spherical shell, I = ⅔ mr².
mgh = ½ mv² + ½ (⅔ mr²) ω²
mgh = ½ mv² + ⅓ mr²ω²
For rolling without slipping, v = ωr.
mgh = ½ mv² + ⅓ mv²
mgh = ⅚ mv²
gh = ⅚ v²
v = √(1.2gh)
v = √(1.2 × 9.81 m/s² × 1.1 m sin 49.0°)
v = 3.13 m/s
The acceleration down the incline is constant, so given:
Δx = 1.1 m
v₀ = 0 m/s
v = 3.13 m/s
Find: t
Δx = ½ (v + v₀) t
t = 2Δx / (v + v₀)
t = 2 (1.1 m) / (3.13 m/s + 0 m/s)
t = 0.704 s
Rounding to two significant figures, it takes 0.70 seconds.
Answer:
Yes, dimensionally the equation is correct.
Explanation:
This equation is the kinematic equation for uniformly accelerated motion, then we study the units of each member to conclude whether it is dimensionally correct.
vi = initial velocity [m/s]
a = acceleration [m/s^2]
t = time [s]
v = final velocity
therefore we have:
[m/s] + [m/s^2]*[t^2], the second term now is m/s
[m/s] + [m/s] = [m/s]
So the analysis is correct.
A fire because you feed it wood, it lives longer but if you give it a drink, water, then it dies.