Answer:
Statement 1 and 3 are correct.
Explanation:
1. The mass moves downward, so the net acceleration of the block is straight downward.
2.The mass is sliding through the globe, so only the force of gravity is acting on the mass which pulls it in downward direction. The force of gravity has two components [mg sin∅] and [mg cos∅].
Answer:
positive reinforcer; negative reinforcer
Explanation:
positive reinforcer; negative reinforcer
Receiving delicious food can be seen as a positive reinforcer while escaping electric shock can be seen as a negative reinforcer.
Answer:
B. +m
Explanation:
The magnification of an image is defined as the ratio between the size of the image and of the object:
where we have
y' = size of the image
y = size of the object
There are two possible situations:
- When m is positive, y' has same sign as y: this means that the image image is upright
- When m is negative, y' has opposite sign to y: this means that the image is upside down
Therefore, the correct option representing an upright image is
B. +m
Answer:
B
Explanation:
Electromagnetic spectrum includes visible light which we see all the time reflecting off objects to give them colours, mechanical waves like sound require something to move in, its the reason why people say you can't scream in space because space is a giant vacuum. No not the kind you use to clean up the mess you made from breakfast. The kind that has no air. So sound can be heard on earth as it is not a vacuum, air moves freely and transfers sounds vibrations all around you to be absorbed by walls and other stuff in comes in contact with.
Extra information:
Sound travels further in water because the molecules are closer together meaning that transferring the energy is easier. This is how Blue wales can communicate from hundreds of miles away.
The final velocity of object 2 is: 3 m/sec
<h3>What is the conservation of mass?</h3>
According to the rule of conservation of mass, no atoms are created or destroyed during a chemical process. Instead, the atoms combine in a variety of ways to create goods. This explains why each element has the equal amount of atoms on both sides of an equation with balanced symbols.
According to conservation of mass,
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
Given that,
m₁ = 50 kg
m₂ = 75 kg
u₁ = 4 m/s
u₂ = -1 m/s
v₁ = -2 m/s
v₂ = ?
Now, putting the values,
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
(50 × 4) + [75 × (-1)] = [50 × (-2)] + (75 × v₂)
or, 125 = -100 + 75 v₂
or, 75 v₂ = 225
or, v₂ = 3 m/sec.
To know more about velocity refer to:
brainly.com/question/80295
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