If you want to tell a friend about a fish you caught or a tree you cut down,
you're going to tell him WHERE you were ... its position in space, 3 numbers,
'x', 'y', and 'z' ... and also WHEN you were ... its position in time, one more
number.
Dimensions are numbers used to describe the location of a point, and the
difference in location between two points. With four numbers, you can exactly
describe the location of anything, and its distance from any other thing, in
space and time.
By striking another object that is free to move, the moving object can exert a force and cause the second object to shift its position. While the object is moving, it has the capacity for doing work. Energy means the ability to do work, so all moving things have energy by virtue of their motion.
Translation: Al golpear otro objeto que se puede mover libremente, el objeto en movimiento puede ejercer una fuerza y hacer que el segundo objeto cambie de posición. Mientras el objeto se mueve, tiene la capacidad de realizar un trabajo. Energía significa la capacidad de realizar un trabajo, por lo que todas las cosas en movimiento tienen energía en virtud de su movimiento.
Answer:
(a) Most reactive
Metal B
Metal D
Metal A
Least reactive
Metal C
(b) (i) Bubbles should form very slowly
(ii) No reaction takes place
Explanation:
(a) The given metals arranged in their order of reactivity are;
Most reactive
Metal B
Metal D
Metal A
Least reactive
Metal C
The other of reactivity is based on the nature of their reactivity of the metals in air
(b) (i) Based on the reactivity of the metals in air, whereby metal A reacts very slowly and an oxide is formed, we have that, based on the reactivity of the metal A, when mixed with dilute hydrochloric acid, bubbles should form very slowly
(ii) Similarly, given that metal C is unreactive, we have that when small pieces of metal C are added to dilute hydrochloric acid, no reaction takes place.
Answer:
a)
b)
c)
d)
m
e)λ=∞
Explanation:
De Broglie discovered that an electron or other mass particles can have a wavelength associated, and that wavelength (λ) is:

with h the Plank's constant (
) and P the momentum of the object that is mass (m) times velocity (v).
a)

b)

c)

d)
m
e) 
λ=∞
Answer:
The frequency is 302.05 Hz.
Explanation:
Given that,
Speed = 18.0 m/s
Suppose a train is traveling at 30.0 m/s relative to the ground in still air. The frequency of the note emitted by the train whistle is 262 Hz .
We need to calculate the frequency
Using formula of frequency

Where, f = frequency
v = speed of sound
= speed of passenger
= speed of source
Put the value into the formula


Hence, The frequency is 302.05 Hz.