Answer:
A. chemical substance whose atoms all have the same number of protons
Explanation:
An element is a substance which contains identical atoms that have the same number of protons in the nucleus.
Elements are arranged in the periodic table according to their atomic number (= number of protons): so atoms of different elements have a different number of protons in their nuclei.
For a neutral atom, the number of electrons around the nucleus is also equal to the number of protons.
Moreover, atoms of the same element can have a different number of neutrons, despite having the same number of protons - these atoms are called isotopes.
The answer is attract. Hope it helps! :)
Answer:
A) Although the speed is the same, the direction has changed. Therefore, the velocity has changed.
Explanation:
Answer:
t = 5 hr
Explanation:
Let kali moves toward east with velocity= V₁= 40 km/ h
Mat moves toward west with velocity = V₂= 50 km/hr
As Klai left one hour earlier = t₁= 1 hr
distance traveled in 1st hour = s₁ = v * t = 40 * 1 = 40 km
Remaining distance = 400 - 40 = 360 km
As they move in the opposite directions:
Relative speed= 40 + 50 = 90 km/ h
s = v * t
⇒ t = s / v
⇒ t₂ = 360 / 90
⇒ t₂ = 4 hr
Total time = t = t₁ + t₂
t = 1 hr + 4 hr
t = 5 hr
