The period of the pendulum doesn't determine the length of the string.
It's the other way around.
The period of the pendulum is proportional to the square root of its length.
So if you want to triple the period, you have to make the string nine times
as long as it is now.
To the Earth in less than ten minutes.
Answer:
Explanation:
The electric field outside the sphere is given as,
E = k Q /r²
here Q = n x 1.6 x 10⁻¹⁹ C
where n is the number of electons
if the dimeter of sphere d= 25 cm= 0.25 m
then the radius r = 0.125 m
we get
n= E r²/ k x 1.6 x 10⁻¹⁹ C
n = 1350N/C x (0.125m)² / (8.99 x 10⁹ N m²/C² x 1.6 x 10⁻¹⁹ C)
n = 14664731646
Answer:
i don't know if this is good for you but
Explanation:
ignoring frictional air resistance (drag) the speed on return is the same as when it left the ground (5 m/s but in the opposite direction).
Note: this points out a good reason for not firing live bullets into the air..they will return somewhere and at the same speed.
However, if you take into account the atmospheric drag the reurn speed will be somewhat smaller (but in the case of a bullet, probably still lethal.) Drag depends on many factors and is difficult to calculate.
Answer:
17.565 kgm/s
Explanation:
Momentum = mass × velocity
I = mv..................... Equation 1
But we can calculate the value of v using the equation of motion under gravity.
v² = u²+2gs............. Equation 2
Where u = initial velocity, s = maximum heigth, g = acceleration due to gravity.
Given: u = 0 m/s (at the maximum heigth), s = 7.0 m.
Constant: g = 9.8 m/s²
Substitute these values into equation 2
v² = 0²+ 2×7×9.8
v² = 137.2
v = √137.2
v = 11.71 m/s.
Also given: m = 1.50 kg
substitute these values into equation 1
Therefore,
I = 1.5×11.71
I = 17.565 kgm/s