They use fans and air conditioning in the summer because its hot, which means they use energy and in the winter, there is no need because its cold so less energy.
Answer:
Forces acting on an object may be balanced or unbalanced. When the forces acting on an object have <u>equal</u> strength and act in opposite directions, they are <u>balanced</u>. These forces cancel out one another, and the <u>motion</u> of the object does not <u>change</u>. When the forces acting on an object are <u>unbalanced</u>, they do not cancel out one another. An unbalanced force acting on an object results in the object’s motion <u>changing</u>. The object may change its <u>speed</u> (speed up or slow
down), or it may change its <u>direction</u>. <u>Friction</u> is a force that resists the motion or the tendency toward motion between two objects in contact with each other. <u>Gravity</u> is a force that pulls objects toward one another. For example, Earth pulls all objects toward it.
Explanation:
Answer : The formula for each of the following is:
(a) 
(b) 
(c) 
Explanation :
- Alkanes are hydrocarbon in which the carbon atoms are connected with single covalent bonds.
The general formula of alkanes is 
where n is the number of the carbon atoms present in a molecule of alkane.
- Alkenes are hydrocarbon in which the carbon atoms are connected with double covalent bonds.
The general formula of alkenes is 
where n is the number of the carbon atoms present in a molecule of alkene.
- Alkynes are hydrocarbon in which the carbon atoms are connected with triple covalent bonds.
The general formula of alkynes is 
where n is the number of the carbon atoms present in a molecule of alkyne.
(a) An alkane with 22 carbon atoms
Putting n = 22 in the general formula of alkane, we get the formula of alkane as, 
or
(b) An alkene with 17 carbon atoms
Putting n = 17 in the general formula of alkene, we get the formula of alkene as, 
or
(c) An alkyne with 13 carbon atoms
Putting n = 13 in the general formula of alkyne, we get the formula of alkyne as, 
or
Answer: c = 710 J/kg°C or 0.71 J/g°C
Explanation: Heat is expressed in the formula Q = mc∆T. Derive to find the specific heat c. So the formula will become c = Q / m∆T
c = Q / m∆T
= 42600 J / 2 kg ( 55°C - 25°C )
= 710 J /kg°C
Or can be expressed by converting kg to g.
c = 0.71 J /g°C
First one is reactants and then second one is products
