Answer:
23. 4375 m
Explanation:
There are two parts of the rocket's motion
1 ) accelerating (assume it goes upto h1 height )
using motion equations upwards
Lets find the velocity after 2.5 seconds (V1)
V = U +at
V1 = 0 +5*2.5 = 12.5 m/s
2) motion under gravity (assume it goes upto h2 height )
now there no acceleration from the rocket. it is now subjected to the gravity
using motion equations upwards (assuming g= 10m/s² downwards)
V²= U² +2as
0 = 12.5²+2*(-10)*h2
h2 = 7.8125 m
maximum height = h1 + h2
= 15.625 + 7.8125
= 23. 4375 m
Let us consider two bodies having masses m and m' respectively.
Let they are separated by a distance of r from each other.
As per the Newtons law of gravitation ,the gravitational force between two bodies is given as - where G is the gravitational force constant.
From the above we see that F ∝ mm' and
Let the orbital radius of planet A is = r and mass of planet is .
Let the mass of central star is m .
Hence the gravitational force for planet A is
For planet B the orbital radius and mass
Hence the gravitational force
Hence the ratio is
[ ans]
Answer:
1977.696 J
Explanation:
Given;
Weight of the box = 28.0 kg
Force applied by the boy = 230 N
angle between the horizontal and the force = 35°
Therefore,
the horizontal component of the force = 230 × cosθ
= 230 × cos 35°
= 188.405 N
Coefficient of kinetic friction, μ = 0.24
Force by friction, f = μN
here,
N = Normal force = Mass × acceleration due to gravity
or
N = 28 × 9.81 = 274.68 N
therefore,
f = 0.24 × 274.68
or
f = 65.9232 N
Now,
work done by the boy, W₁ = 188.405 N × Displacement
= 188.405 N × 30
= 5652.15 J
and,
the
work done by the friction, W₂ = - 65.9232 N × Displacement
= - 65.9232 N × 30 m
= - 1977.696 J
[ since the friction force acts opposite to the direction of motion, therefore the workdone will be negative]
The reaction 4Al + 3O₂ → 2Al₂O₃ is a synthesis or also called combination reaction because reactants combine to produce a new compound (Option 2).
<h3>What is a synthesis combination reaction?</h3>
In chemistry, a synthesis or combination reaction is any type of chemical reaction in which two or more molecules called reactants combine to produce one or more molecules called products of such reaction.
Therefore, with this data, we can see that a synthesis or combination reaction is a chemical process where two or more molecules combine to produce a new molecule known as a product.
Learn more about synthesis combination reactions here:
brainly.com/question/14703806
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