Answer: electric field
Explanation: when a charge is placed in space, it alters the space around it by creating an electric field.
This electric field has the ability to exert a force (f) on any test charge(q) placed within this vicinity.
This is the reason why a charge can either attract or repel another charge.
Answer:
mass.
Explanation:
other physical factors are changeable but the mass of a particular substance is always constant.
2.5 kg because you cant change the weight of the rock
Answer: bismuth and nitrogen, because they have the same number of valence electrons
Explanation:
Elements are distributed in groups and periods in a periodic table.
Elements that belong to same groups will show similar chemical properties because they have same number of valence electrons.
The number of valence electrons in Bismuth and nitrogen are 5 and thus thus they will show similar chemical properties and thus belong to the same group.
The atomic masses of elements in a group will differ drastically.
The group number has got nothing to be the isolation year.
Thus bismuth and nitrogen belong to same group because they have the same number of valence electrons
Answer:
External force on him = 257.40 N
Equation is; F = ma (where 'f' is force, 'm' is mass and 'a' is acceleration)
Explanation:
The mass of the sprinter is 58.5 kg
His acceleration is 4.40 m/s²
According to Newton's second law of motion; F = ma
External force on the sprinter = 58.5 kg × 4.40 m/s² = 257.40 N