5.5 s
Explanation:
The time it takes for the ball to reach its maximum height can be calculated using
since 
at the top of its trajectory. Plugging in the numbers,
Answer:
(a) There are 3.17 times more shakes in a second than seconds in a year.
(b) Humans have existed for 9067.72 universe seconds.
Explanation:
(a) First we calcule how many seconds are in a year. One year have 365 days, one day has 24 hours, one hour has 60 minutes and one minute has 60 seconds, so:
Now, we calculate how many shakes are in a second:
Finally, we calculate how many more shakes in a second are there than seconds in a year:
(b) Using a simple rule of three we can calculate how many "universe seconds" have humans existed, recall that 1 day has 86400 seconds:
1010 years--------->86400s
106 years----------> x seconds
1) sound velocity reported by you : 292.39 m /s
2) time to travel 1620m at that velocity: t = d / v = 1620 m / 292.39 m/s = 5.54 s, since the moment the sound wave started.
3) You might wanted to tell the time since you watched the lightning.
Then you can calculate the time since the lighting was generated,1620 m away from you, until you saw it, using the speed of light:
speed of light = 3*10^8 m/s => t = 1620 m / (3*10^8m/s) =0.0000054 s
Then, this time is completely neglectible, and yet the answer is 5.54 s, as calculated in the step 2.
Answer:
Explanation:
Moment of inertia of the rod = 1/12 m L²
m is mass of the rod and L is its length
= 1/2 x 2.3 x 2 x 2
= 4.6 kg m²
Moment of inertia of masses attached with the rod
= m₁ d² + m₂ d²
m₁ and m₂ are masses attached , and d is their distance from the axis of rotation
= 5.3 x 1² + 3.5 x 1²
= 8.8 kg m²
Total moment of inertia = 13.4 kg m²
B )
Rotational kinetic energy = 1/2 I ω²
I is total moment of inertia and ω is angular velocity
= .5 x 13.4 x 2²
= 26.8 J .
C )
when mass of rod is negligible , moment of inertia will be due to masses only
Total moment of inertia of masses
= 8.8 kg m²
D )
kinetic energy of the system
= .5 x 8.8 x 2²
= 17.6 J .
