Is gaining weight gaining mass?

In summary, mass can be increased by eating more food, building more muscle, or losing weight through exercise.
  • #1
jimmy1200
46
0
im still confused on this, can someone put the knowledge smack down on me.
 
Biology news on Phys.org
  • #2
yes

F=ma
since a stays the same
mass must increase
since weight... pounds is a measure of force.
 
  • #3
i thought mass cannot be created or destroyed
 
  • #4
When you eat, you are adding new mass to your body.

Some of it you convert to energy, some of it you use for growth/maintainance (e.g., building new cells), some you store (i.e., fat cells), and some you expel (undigestable stuff).

As Tom said, "weight" is just mass x gravity. You weigh more on the surface of the Earth than you would on the surface of the moon because of the differences in gravity here and there. But your mass is unchanged in those two cases. Your mass is how much stuff you are made of.

You can add mass to your body by eating more food to store more (e.g., fat cells) or build more (e.g., muscle cells). You can lose mass by eating less and/or exercising in which case your body will burn up some fat cells. That mass is lost through conversion to energy, sweating, respiration, etc.

Consider the growth of a baby to an adult. A lot of mass is being added. From where? Food.
 
  • #5
No.

Gaining weight is not necessarily gaining mass in Newtonian mechanics. I don't know enough about GR to comment on weight in relativity.

Weight is the amount of force with which gravity acts on an object. Newton indicates that the magnitude of gravity is:
[tex]\frac{m_1 \times m_2 \times G}{r^2}[/tex]

There are four variables in this formula which suggests that there are four methods for changing weight:
Changing the mass of one object. This is what you suggested as a means of changing weight.
Moving further apart. Clearly, as [tex]r[/tex] gets larger the force of gravity on an object - or the weight of that object - gets smaller. An astronaut on the space shuttle weighs less than he does on the surface without an appreciable change in mass. Objects in deep space have almost no weight at all.
Changing the other mass. The mass of the Moon is roughly one sixth of the mass of the Earth. Consequently the force of gravity on an object due to the Moon is approximately one sixth that of that due to the Earth.
Changing the gravitational constant [tex]G[/tex]. Although physics suggests that it's extremely unlikely, it is concievable that the gravitational constant may chang over time. An objects weight could be changed by the gravitational constant changing.
 
  • #6
If you are talking about a situation where the surroundings are constant and you gain mass, then mass and weight would increase/decrease together.
 
  • #7
i thought that weight=mass x gravity. so, i'd think that in order to keep the two equal, mass would have to increase becase gravity is constant. Weight/gravity=mass... is that wrong? that's what i was taught, at least.
 
  • #8
jimmy1200 said:
i thought mass cannot be created or destroyed
First off, the correct statement is "energy cannot be created nor destroyed".

Like the previous posters said, weight is just a measurement of the force exerted on you by gravity and this force is proportional to your mass.
 
  • #9
doxigywlz said:
i thought that weight=mass x gravity. so, i'd think that in order to keep the two equal, mass would have to increase becase gravity is constant. Weight/gravity=mass... is that wrong? that's what i was taught, at least.
Ok, so the proposition is that if you go to a planet where gravity is smaller, your weight will be smaller. Also, in order to lower your weight you have to either lower your mass and/or lower the acceleration due to gravity.
 

1. What is the difference between gaining weight and gaining mass?

Gaining weight refers to an increase in body weight, which can be due to an increase in fat, muscle, or water. Gaining mass, on the other hand, specifically refers to an increase in muscle mass. While gaining weight can be achieved through both fat and muscle gain, gaining mass is typically associated with an increase in muscle mass only.

2. Can gaining weight also mean gaining muscle mass?

Yes, gaining weight can also mean gaining muscle mass. This is because muscle is denser than fat, so even if you are gaining weight, you may be losing fat and gaining muscle at the same time. This is often seen in people who are following a strength training program and are gaining weight due to an increase in muscle mass.

3. How does gaining weight affect overall body composition?

Gaining weight can affect overall body composition by increasing the amount of fat and muscle in the body. This can change the body's appearance and may also impact overall health. It is important to consider the source of weight gain (fat vs. muscle) and maintain a balanced diet and exercise routine to achieve a healthy body composition.

4. Is gaining weight always a bad thing?

No, gaining weight is not always a bad thing. In fact, for some individuals, gaining weight may be necessary for their overall health and well-being. This can be true for individuals who are underweight or have certain medical conditions that require weight gain. It is important to consult with a healthcare professional to determine what is a healthy weight for your body.

5. Can gaining weight be harmful to overall health?

While gaining weight can be beneficial for some individuals, it can also be harmful to overall health if it is due to excess fat gain. This can increase the risk of obesity, heart disease, and other health problems. It is important to maintain a balanced diet and exercise regularly to ensure that any weight gain is from healthy sources and does not negatively impact overall health.

Similar threads

  • Biology and Medical
Replies
20
Views
1K
  • Biology and Medical
Replies
16
Views
2K
  • Classical Physics
Replies
29
Views
1K
  • Biology and Medical
Replies
9
Views
2K
  • Classical Physics
Replies
14
Views
645
  • Special and General Relativity
Replies
25
Views
2K
Replies
28
Views
1K
  • Biology and Medical
Replies
6
Views
4K
  • Introductory Physics Homework Help
Replies
2
Views
776
Back
Top