The complete question is as follows: A student is subjected to a reaction force of 10 N northward from a 5 kg block while pushing the block over a smooth, level surface. Ignoring friction, what is the acceleration of the block?
Answer: The acceleration of the block is 
.
Explanation:
Given: Force = 10 N
Mass = 5 kg
It is known that force applied on an object is the product of mass and acceleration.
Mathematically, 
where,
F = force
m = mass
a = acceleration
Substitute the values into above formula as follows.
Thus, we can conclude that the acceleration of block is .
Answer:
The arrow will leave the bow with a velocity of 10 m/s.
Explanation:
Hi there!
The potential energy stored in the bow can be calculated using the following equation:
U = 1/2 · k · d²
Where
U = elastic potential energy.
k = spring constant.
d = stretched distance of the bow
Then:
U = 1/2 · 112 N/m · (0.29 m)²
U = 4.7 J
When the bow is released, the potential energy is transformed into kinetic energy. Then, the kinetic energy of the arrow when it leaves the bow will be:
KE = 1/2 · m · v² = 4.7J
Where:
KE = kinetic energy.
m = mass of the arrow.
v = velocity of the arrow:
Then:
4.7 J = 1/2 ·0.094 kg · v²
2 · 4.7 J / 0.094 kg = v²
9.4 kg · m²/s² / 0.094 kg = v²
v = 10 m/s
The arrow will leave the bow with a velocity of 10 m/s.
Answer: A. Object A will have a positive charge.
Explanation: If the number of protons and electrons are the same, their net charges cancel each other out, and you have a neutral charge. If electrons are transferred to another object, the amount of positive charge will outweigh the amount of negative charge. As a result, you are left with an overall positive charge in object A. Meanwhile, object B is now negative.
Answer:
1.89*10⁶J
Explanation:
because 4500kg * 42m*10m/s² is 1890000J
The energy required to start a reaction IS called the activation energy. TRUE
