Answer:
F = - k (x-xo) a graph of the weight or applied force against the elongation obtaining a line already proves Hooke's law.
Explanation:
The student wants to prove hooke's law which has the form
F = - k (x-xo)
To do this we hang the spring in a vertical position and mark the equilibrium position on a tape measure, to simplify the calculations we can make this point zero by placing our reference system in this position.
Now for a series of known masses let's get them one by one and measure the spring elongation, building a table of weight vs elongation,
we must be careful when hanging the weights so as not to create oscillations in the spring
we look for the mass of each weight
W = mg
m = W / g
and we write them in a new column, we make a graph of the weight or applied force against the elongation and it should give a straight line; the slope of this line is sought, which is the spring constant.
The fact of obtaining a line already proves Hooke's law.
Answer:
13 km
Explanation:
The bird flies from the runner, to the finish line, and back to the runner. We can write two equations for the distance it travels:
d = 7.8 km + 7.8 km − 4.9 km/hr × t
d = 24.5 km/hr × t
Solve for t in the second equation and substitute into the first:
t = d / 24.5
d = 7.8 + 7.8 − 4.9 (d / 24.5)
d = 15.6 − 0.2 d
1.2 d = 15.6
d = 13
The bird flies a cumulative distance of 13 km.
A star is a large ball of gas that generates its own energy by fusing hydrogen atoms to make helium. It is held together by its own gravity. ... Stars come in a variety of sizes and compositions, which determine their amount of energy and gravity.
Answer:
b-energy is not exchanged
Explanation:
An isolated system is a thermodynamic system in which neither energy nor matter is exchanged with the surroundings.
As such the best statement that will fill the box under an isolated system is that energy is not exchanged.
- In an open system, both matter and energy are exchanged with the surrounding.
- A closed system is one in which energy transfer is permissible but matter is not exchanged.
- Energy cannot be created nor destroyed in any system. They are simply transformed.
Answer:
The two balls meet in 1.47 sec.
Explanation:
Given that,
Height = 25 m
Initial velocity of ball= 0
Initial velocity of another ball = 17 m/s
We need to calculate the ball
Using equation of motion

Where, u = initial velocity
h = height
g = acceleration due to gravity
Put the value in the equation
For first ball
....(I)
For second ball
....(II)
From equation (I) and (II)



Hence, The two balls meet in 1.47 sec.