Answer:
it cannot be considered a physical change because it occur from the chemical reaction.
Explanation:
because physical change is the change of the size,volume, density,flexibility. in other words its a change in the outer appearance or change in which we can see or feel without using a tool or a machine
hope it help just my opinion
1. Answer:
The relationship between Force A and Force B is given as:
A = B
Explanation:
To produce acceleration to a body, an unbalanced force must be applied. Meaning that a Force must be applied to the body greater than that of Force of Friction.
In our case, a Force A is exerted on the crate which is moving with a constant velocity. As there is no acceleration, the force applied must be equal to the force of Friction B.
2. Answer:
The electron's acceleration is 1.756 x 10¹⁷ ms⁻².
Explanation:
Electric field exerts a Force on the electron given as:
F = 1.6 x 10⁻¹³ N
Rest mass of electron = 9.11 x 10⁻³¹ kg
According to newton's 2nd law of motion, a net force F applied on the electron must produce an acceleration 'a' which is directly proportional to the Force and inversely proportional to the rest mass of the electron given as:
a = F/m
a = (1.6 x 10⁻¹³)/(9.11 x 10⁻³¹)
a = 1.756 x 10¹⁷ ms⁻²
Light year is the distance traveled by light in 1 year of time interval
so here we can say that the statement must have used the word light year as the distance
so we have
A) It's about 4 light-years from here to Alpha Century.
this shows the distance between two so it is correct
B) It will take me light-years to complete this homework assignment.
here it represent the light year as time so it is INCORRECT
C) A light-year is about 10 trillion kilometers.
This shows the distance so it is correct
D) It will take the Voyager spacecraft about 20,000 years to travel just 1 light-year.
It shows the distance so it is correct
E) The Milky Way Galaxy is about 100,000 light-years in diameter.
this is distance so it is also correct
Answer:
f = 6.912 E14 Hz
Explanation:
The speed of the wave is defined as
speed = wavelength*frequency
the frequency of the photon is defined as
f = speed / wavelength
f = 3 E8 m/s / 434 E-9 m
f = 6.912 E14 Hz