Answer:
Explanation:
- We have to make a hollow sphere of inner radius
and outer radius 
.
Then the mass of the material required to make such a sphere would be calculated as:
Total volume of the spherical shell:
And the volume of the hollow space in the sphere:
Therefore the net volume of material required to make the sphere:
- Now let the density of the of the material be
.
<u>Then the mass of the material used is:</u>
Multiply it by a fraction equal to ' 1 ', like this:
(14.8 cm) x (1 meter/100 cm) = 14.8/100 = 0.148 meter
Answer:
because it undergo combustion
Explanation:
and when combustion takes place high amount of energy is released
Answer:
The ball takes 5s to reach the ground
Explanation:
in order to solve this problem we use the kinematics equation with gravity as acceleration:
we replace the values
We solve this quadratic equation:
t=5s
t=-6s (this solution has not physical sense)
Answer:
870 N
Explanation:
The expression for velocity of wave in a string is given below
v = 
, T is tension and m is mass per unit length .
m = 45 x 10⁻³ / 30 x 10⁻²
= .15 kg/m
Putting the given values in the equation
76 = 
T = 76² x .15
= 866.4
870 N approx.
