Answer:
Muscles work in pairs to move a bone.
Skeletal muscles only PULL in one direction. For this reason they always come in pairs. When one muscle in a pair contracts, to bend a joint for example, its counterpart then contracts and pulls in the opposite direction to straighten the joint out again.
Answer:
Explanation:
It can be determined by measuring the Ph. D is incorrect.
C: is wrong because if you are making something acidic, you are increasing the H+
B: is the correct answer.
A: pH decreases. H+ increases which makes the Ph decrease. It is an oddity of the formula that makes this happen.
Answer:
, 
Explanation:
The change in energy is given by the change in gravitational potential energy:
The average rate of change in terms of time is approximately this:
Answer:
a) 2.173
b) 20ml
c) 3.87
d) 4.35
e) 8.8
f) 12.45
Explanation:
chech the attachment for explanationns
Answer:
Bohr's model of the hydrogen atom is based on three postulates:
1) An electron moves around the nucleus in a circular orbit,
2) An electron's angular momentum in the orbit is quantised,
3) The change in an electron's energy as it makes a quantum jump from one orbit to another is always accompanied by the emission or absorption of a photon. Bohr's model is semi-classical because it combines the classical concept of electron orbit (postulate 1) with the new concept of quantisation ( postulates 2 and ).
