Answer:
Magnetic: Magnet being pulled to a metal surface- non- contact force
Friction: skateboard slowing down on a rough surface- contact force
Gravity: Ball falling to the ground - non-contact force
Electrical: Charged balloon pulling up on arm hair - non- contact force
Tension (pull): people playing tug-of-war - contact force
Applied (push): a person pushing a toy car - contact force
Air resistance: wind pushing on the sail of a sailboat - contact force
Spring: springs being pushed together -contact force
Explanation:
A contact force is a type of force that can only act when two bodies touch other physically. Examples of this include a push or a pull.
A non-contact force is a type of force that can only act when two bodies do not touch other physically. Examples include; electric force, magnetic force, etc.
The correct option is 58 Fe 2+.
A neutral atom normally has the same number of proton, neutron and electrons, if the number of electrons differ from that of proton, that means that the elements has given some electrons away or it has gained some electrons from another element.
In the question given above, the atomic number of the element is 26 [because the proton number is 26], which means the element is iron. Iron has 24 electrons because it has given two away, so it will have +2. The iron has 32 neutrons instead of 26 so it is an isotope.
Explanation:
Correct option is
D
3
The unbalanced chemical reaction is Al(s)+O
2
(g)→Al
2
O
3
(s)
Balance Al atoms by adding 2 to Al on LHS
2Al(s)+O
2
(g)→Al
2
O
3
(s)
Balance O atoms by adding
2
3
to O
2
on LHS
2Al(s)+
2
3
O
2
(g)→Al
2
O
3
(s)
Multiply the whole equation with 2.
4Al(s)+3O
2
(g)→2Al
2
O
3
(s)
This is the balanced chemical equation. The coefficient of O
2
is 3.
Usually, they aren't found in the same place because fossils are already very rare. For every 1 billion humans, there would only be one fossil. So the odds would be very slim for them both to be found in the same place.
Hope I helped!
Let me know if you need anything else!
~ Zoe