The amount of matter in an object ismass....anything that occupies spaca and has weight is called matter.....
Answer:
Explanation:
If air resistance is ignored and assume UP and Toward Jason are the positive directions.
horizontal analysis
d = (vx₀)t
t = d/vx₀
horizontal analysis
0 = vy₀t + ½gt²
0 = vy₀(d/vx₀)+ ½g(d/vx₀)²
as vy₀ = v₀sin45 and vx₀ = v₀cos45 and are equal.
0 = d + ½g(d²/v₀²cos²45)
-d = ½g(d²/v₀²cos²45)
-dv₀² = ½g(d²/cos²45)
v₀² = -½g(d/cos²45)
v₀² = -½(-9.81(32.0/cos²45)
v₀² = 313.92
v₀ = 17.717787...
v₀ = 17.7 m/s
Momentum is conserved, so the sum of the separate momenta of the car and wagon is equal to the momentum of the combined system:
(1250 kg) ((36.2 <em>i</em> + 12.7 <em>j </em>) m/s) + (448 kg) ((13.8 <em>i</em> + 10.2 <em>j</em> ) m/s) = ((1250 + 448) kg) <em>v</em>
where <em>v</em> is the velocity of the system. Solve for <em>v</em> :
<em>v</em> = ((1250 kg) ((36.2 <em>i</em> + 12.7 <em>j </em>) m/s) + (448 kg) ((13.8 <em>i</em> + 10.2 <em>j</em> ) m/s)) / (1698 kg)
<em>v</em> ≈ (30.3 <em>i</em> + 12.0 <em>j</em> ) m/s
The correct answer is B.
Let us think of the classical theory first. In the classical theory, light is a wave that gives energy. This energy gradually helps the electron jump to a higher energy level.
In quantum theory, this is wrong; an electron cannot absorb a small amout of energy because there is not close enough state to jump to with that energy; only very specific amounts of energy lead to a change in orbital levels/ absorbance of energy. Also, each pair of energy levels has a specific energy difference that is needed from an electron so that it can move.
Hence, B is correct; all other sentences describe classical models of light-electron interactions
Answer:
work done he has done is equal to 6452.712 J
Explanation:
given,
Assume the mass of the cheerleader be equal to 70.8 kg
she is lift up off to the height of 0.31 m
acceleration due to gravity = 9.8 m/s²
number of time she was lift = N = 30 times
work done = N W
W = m g h
work done = N m g h
work done = 30 x 70.8 x 9.8 x 0.31
= 6452.712 J
hence, work done he has done is equal to 6452.712 J