This is the same question that I just answered.
Have present the definition of acceleration:
a = Δv / Δt, this is change in velocity per unit of time.
a and v are in bold to mean that they are vectors.
1) a body traveling in a straight line and increasing in speed: CORRECT:
Acceleration is the change in velocity, either magnitude or direction or both. So, a body increasing in speed is accelerated.
2) a body traveling in a straight line and decreasing in speed: CORRECT
A decrease in speed is a change in velocity, so it means acceleration.
3) a body traveling in a straight line at constant speed: FALSE.
That body is not changing either direction or speed so its motion is not accelerated but uniform.
4) a body standing still : FALSE.
That body is not changind either direction or speed.
5) a body traveling at a constant speed and changing direction: CORRECT.
The change in direction means that the body is accelerated. The acceleration due to change in direction is named centripetal acceleration.
<span>net work = change in kinetic energy
for Block B, we just have the force from block A acting on it
F(ab)d= .5(1)vf² - .5(1)(2²)
F(ab)d= .5vf² - 2
Block A, we have the force from the hand going in one direction and the force of block B on A going the opposite direction
10-F(ba)d = .5(4)vf² - .5(4)(2²)
10-F(ba)d = 2vf² - 8
F(ba)d = 18 - 2vf²
now we have two equations:
F(ba)d = 18 - 2vf²
F(ab)d= .5vf² - 2
since the magnitude of F(ba) and F(ab) is the same, substitute and find vf (I already took into account the direction when solving for F(ab)
10-.5vf² + 2 = 2vf² - 8
12 - .5vf² = 2vf² - 8
20 = 2.5vf²
vf² = 8
they both will have the same velocity
KE of block A= .5(4)(2.828²) = 16 J
KE of block B=.5(1)(2.828²) = 4 J</span>
Answer:
a. Stars all warm objects
c. Some unstable atomic nuclei
Explanation:
Gamma rays are photons of very high energy (beyond 100keV) enough to remove an electron from its orbit.
They have a very short wavelength, less than 5 meters from the peak, and can be produced by nuclear decay, especially in the breasts of massive stars at the end of life.
They were discovered by the French chemist Paul Villard (1860 to 1934).
While X-rays are produced by electronic transitions in general caused by the collision of an electron with an atom at high speed, gamma rays are produced by nuclear transitions.
Gamma rays produce damage similar to those caused by X-rays or ultraviolet rays (burns, cancer and genetic mutations).
The sources of gamma rays that we observe in the universe come from <u>massive stars (hypernovas) or some warm objects on the space</u> that end their lives by a gravitational collapse that leads to the formation of a neutron star or a black hole, as well as <u>unstable radioactive nuclei </u>that emit radiation gamma to reach its steady state.
Answer:he's not applying force or motion
Explanation:
p=f & m
Answer:
The speed of the top of the wheel is twice the speed of the car.
That is: 72 m/s
Explanation:
To find the speed of the top of the wheel, we need to combine to velocities: the tangential velocity of the rotating wheel due to rotational motion 
- with 
being the wheel's angular velocity,
plus the velocity due to the translation of the center of mass (v = 36 m/s).
The wheel's angular velocity (in radians per second) can be obtained using the tangential velocity for the pure rotational motion and it equals:
Then the addition of these two velocities equals:
