Answer:
4.2 m
Explanation:
Note: If energy is conserved, i.e no work is done against friction
Work input = work output.
Work output = Force output × distance,
Work input = force input × distance moved moved.
Therefore,
input force×distance moved = output force × distance moved........................Equation 1
Given: input force = 80 N, output force = 240 N, output distance = 1.4 m
Let input distance = d
Substitute into equation 1
80×d = 240×1.4
80d = 336
d = 336/80
d = 4.2 m.
Thus the rope around the pulley must be pulled 4.2 m
1. Ca → Element
2. Proton → positive
3. H2O → compound
4. Fission → nuclear decay
5. Fusion → Nuclear synthesis
6. η → Neutron
7. e → electron
8. Atomic number → no of protons in nucleus.
Explanation
1. Ca (Calcium):
Calcium is an element with the atomic number of 20. It is an alkaline earth metal. The 99% of calcium is found in our bodies, in bones, teeth.
2. Proton:
Proton is a subatomic particle and it holds the positive charge. Proton is present in the nucleus of the atom.
3. H2O (water):
Water is a chemical compound and it's chemical formula is H2O. It's called compound as it contains 2 hydrogen and 1 oxygen atoms bonded together through the covalent bond.
4. Fission:
Fission is a process in which large massive unstable nucleus splits into the smaller, less heavier and stable nuclei. The energy is re;eased in the form of radiations during this process. It's called as the radioactive decay.
5. Fusion:
Fusion is opposite of the fission reaction. As in this case the two nuclei combines to form a single large nucleus. That's why it is a nuclear synthesis process.
6. η neutron:
Neutron is a subatomic particle and it is a neutral particle which is located inside the nucleus. n is a symbol used for the neutron.
7. e Electron:
The symbol for electron is e. It's a subatomic particle with negative charge. It is found in the orbits around the nucleus.
8. Atomic Number:
Atomic number is defined as the number of protons in the nucleus of an atom. IT is represented by Z.
Answer:35.2 ft
Explanation:
Given
height of stick =4 ft
shadow length =2.8 ft
Angle of elevation of sun is
let the height of tree be h
as 
will remain same thus
h=35.2 ft
Answer:
Explanation:
Given that,
The initial speed of a car, u = 0
Time, t = 18 s
Distance, d = 390 m
We need to find the acceleration of the car. Let it is a. Using the second equation of motion to find it.
or
So, the acceleration of the car is 
.
You can use the impulse momentum theorem and just subtract the two momenta.
P1 - P2 = (16-1.2)(11.5e4)=1702000Ns
If you first worked out the force and integrated it over time the result is the same
