Answer:
When white light strikes a colored opaque object, some colors of light are absorbed and some are reflected. ... Some of the colors are absorbed and some are reflected. When white light shines on a white object, all colors are reflected. When white light strikes a black object, all colors are absorbed.
Explanation:
Answer:3.67 s
Explanation:
Given
Ball is thrown with an initial velocity of 
As the ball moves upward it experience a declaration due to gravity which will slow down the ball
using

where v=final velocity
u=initial velocity
a=acceleration
t=time
Here 



The characteristics of the scalar product allows to find the angle between the two vectors is:
The scalar product is the product between two vectors whose result is a scalar.
A . B = |A| |B| cos θ
Where A and B are the vectors, |A| and |B| are the modules of the vectors and θ at the angle between them.
The vector is given in Cartesian coordinates and the unit vectors in these coordinates are perpendicular.
i.i = j.j = 1
i.j = 0
A . B = (4 i - 4j). * -5 i + 7j)
A . B = - 4 5 - 4 7
A. B = -48
We look for the modulus of each vector.
|A| =
|A| =
|A| = 4 √2
|B| =
|B| = 8.60
We substitute.
-48 = 4√2 8.60 cos θ
-48 = 48.66 cos θ
θ = cos⁻¹
θ = 170º
In conclusion using the dot product we can find the angle between the two vectors is:
Learn more about the scalar product here: brainly.com/question/1550649
Answer: A. Object A will have a positive charge.
Explanation: If the number of protons and electrons are the same, their net charges cancel each other out, and you have a neutral charge. If electrons are transferred to another object, the amount of positive charge will outweigh the amount of negative charge. As a result, you are left with an overall positive charge in object A. Meanwhile, object B is now negative.
Answer:
1. 98 N
2. 51.0 m
Explanation:
masa 25 kg
velocidad 20 m/s
coeficiente de rozamiento .4
<u>Fuerza de rozamiento:</u>
mu * N, where mu = coeficiente de rozamiento, N = fuerza normal
Calcula N:
F = ma = 25 * -9.8 = -245 N
F rozamiento = mu * N = .4 * -245 = -98 N
<u>Espacio que recorrerá:</u>
F rozamiento = ma
-98 = 25a
a = -3.92 de-aceleración de la fuerza
vf = 0 m/s
vf = at + vi
0 = -3.92t + 20
t = 5.10 seg
x = 1/2 at^2 + vi*t
= 1/2 * -3.92 * 5.10^2 + 20*5.10
= 51.0 m