Answer:
E = 1.711 MeV
Explanation:
From the law of the conservation of energy:
where,
the kinetic energy of positron and electron = 1.2 MeV
Rest energy of the electron and the positron = 0.511 MeV
E = Energy of Photon = ?
Therefore,
<u>E = 1.711 MeV</u>
Answer:
Explanation:
If friction is neglected, the wheel cannot roll and can only slide frictionlessly and will have the same velocity at the bottom of the ramp as if it had been in free fall as it has converted the same amount of potential energy.
mgh = ½mv²
v = √(2gh) = √(2(9.81)(2.00)) = 6.26418... = 6.26 m/s
However if we do not ignore all friction and the wheel rolls without slipping down the slope, the potential energy becomes linear and rotational kinetic energy
mgh = ½mv² + ½Iω²
mgh = ½mv² + ½(½mR²)(v/R)²
2gh = v² + ½v²
2gh = 3v²/2
v = √(4gh/3) =√(4(9.81)(2.00)/3) = 5.11468... = 5.11 m/s
Answer:
f = 6.37 Hz, T = 0.157 s
Explanation:
The expression you have is
y = 5 sin (3x - 40t)
this is the equation of a traveling wave, the general form of the expression is
y = A sin (kx - wt)
where A is the amplitude of the motion, k the wave vector and w the angular velocity
Angle velocity and frequency are related
w = 2π f
f = w / 2π
from the equation w = 40 rad / s
f = 40 / 2π
f = 6.37 Hz
frequency and period are related
f = 1 / T
T = 1 / f
T = 1 / 6.37
T = 0.157 s
Answer:
4.2 m/s
Explanation:
The velocity-time graph is piecewise linear. The acceleration in each of the three segments of the graph is uniform. The instant lies between and t = 6.0s 100 s, so the acceleration must be calculated using the slope of the middle segment.
a =
(9.6 -2.4)m/s
------------------
(10.0 -6.0)s
= 1.8 m/s2
The instantaneous velocity is to be found after the object accelerates over an interval T = (7.0 - 6.0) s = 1.0 s, starting from a velocity of 2.4 m/s,
So the velocity at t = 7.0 s is
v = u + aT = 2.4 m/s + (1.8 m/s2)(1.0 s) = 4.2 m/s
Like this:
1). Ignore the 22.7 m/s horizontal speed. It doesn't make a bit of difference, and the answer doesn't depend on it. (A bullet fired horizontally from a rifle and another bullet dropped from the end of the rifle barrel at the same time both hit the ground at the same time.)
2). Calculate how long it takes an object dropped from rest to fall 42.3 m. Use the "dropped from rest" formula:
Distance = (1/2) (acceleration) (time)²
3). In the formula, "acceleration" is the acceleration of gravity. If this story happened on Earth, then use the acceleration of gravity on Earth. That's 9.81 m/s² .
I wish I could make it more complicated for you, but I don't know how.
