I am quite sure the first one is Friction, but I am not sure about the second one. Is it wind?
ANSWER:
- Transported by blood picked up in the alveoli
- Pumped to cells by ventricles
Hope this helps! :)
Answer:
1.
Upon analysis of the results, a hypothesis can be rejected or modified, but it can never be proven to be correct 100 percent of the time. For example, relativity has been tested many times, so it is generally accepted as true, but there could be an instance, which has not been encountered, where it is not true.
2.Mass is the amount of matter in a body, normally measured in grams or kilograms etc. Weight is a force that pulls on a mass and is measured in Newtons. So on Earth, Weight would be your (mass x acceleration( 9.8 ) . Density, there are lots of kinds of density I guess, but the one you are talking about is density = mass / volume. Density basically means how much mass is occupied in a specific volume or space. Different materials of the same size may have different masses because of its density. Density in this case is measured in kg / m^3 or kg / L or g / m^3 etc where the numerator is a unit of mass and the denominator a unit of volume.
3.The density of an object determines whether it will float or sink in another substance. An object will float if it is less dense than the liquid it is placed in. An object will sink if it is more dense than the liquid it is placed in.
4. An object will float if the gravitational (downward) force is less than the buoyancy (upward) force. So, in other words, an object will float if it weighs less than the amount of water it displaces. This explains why a rock will sink while a huge boat will float.
5.
The momentum of the second ball was 15 kg.m/s.
<h3>What is inelastic collision?</h3>
In which collision some amount of kinetic energy of the system is lost that called inelastic collision. In purely inelastic collision, two bodies stick together. But principle of conservation of linear momentum is obeyed.
In the given question,
Two balls collide and after collision, the final momentum of the system = 18 kg.m/s.
Initial velocity of 1st ball of mass 3 kg is 1 m/s.
So, Initial momentum of first ball = mass × velocity = (3 kg) × (1 m/s) = 3 kg.m/s.
According to Principle of conservation of linear momentum for this inelastic collision,
Initial momentum of first ball + initial momentum of second ball = final momentum of the system
⇒ initial momentum of second ball = final momentum of the system - Initial momentum of first ball
= 18 kg.m/s - 3 kg.m/s.
= 15 kg.m/s.
Hence, initial momentum of second ball = 15 kg.m/s.
Learn more about momentum here:
brainly.com/question/24030570
#SPJ2
Answer:
0.39
Explanation:
In order not to slide, you must have exactly the same acceleration of the train:
where
g = 9.81 m/s^2
There is only one force acting on you: the static frictional force that "pulls" you forward, and it is given by
According to Newton's second law, the net force acting on you (so, the frictional force) must be equal to your mass times the acceleration, so we have
from which we find
so, the minimum coefficient of static friction must be 0.39.
