Answer:20
Explanation: i konw this stuff
Answer:
Explanation:
we know that half life of an element is
T=0.693/λ
where λ is decay constant in order to find decay constant
λ=0.693/T
λ=0.693/8.04
λ=0.086
Explanation:
(10) Mass of a soccer player, m = 0.42 kg
Initial speed, u = 0
Final speed, v = 32.5 m/s
Time, t = 0.21 s
We need to find the force that sends soccer ball towards the goal.
Force, F = ma
So, 65 N of force soccer ball sends towards the goal.
(11) Mass of the satellite, m = 72,000 kg
Initial speed, u = 0 m/s
Final speed, v = 0.63 m/s
Time, t = 1296 s
We need to find the force is exerted by the rocket on the satellite.
Force, F = ma
So, 35 N of the force is exerted by the rocket on the satellite.
Hence, this is the required solution.
Incomplete question.The Complete question is here
A flat uniform circular disk (radius = 2.00 m, mass = 1.00 ✕ 102 kg) is initially stationary. The disk is free to rotate in the horizontal plane about a friction less axis perpendicular to the center of the disk. A 40.0-kg person, standing 1.25 m from the axis, begins to run on the disk in a circular path and has a tangential speed of 2.00 m/s relative to the ground.
a.) Find the resulting angular speed of the disk (in rad/s) and describe the direction of the rotation.
b.) Determine the time it takes for a spot marking the starting point to pass again beneath the runner's feet.
Answer:
(a)ω = 1 rad/s
(b)t = 2.41 s
Explanation:
(a) initial angular momentum = final angular momentum
0 = L for disk + L............... for runner
0 = Iω² - mv²r ...................they're opposite in direction
0 = (MR²/2)(ω²) - mv²r
................where is ω is angular speed which is required in part (a) of question
0 = [(1.00×10²kg)(2.00 m)² / 2](ω²) - (40.0 kg)(2.00 m/s)²(1.25 m)
0=200ω²-200
200=200ω²
ω = 1 rad/s
b.)
lets assume the "starting point" is a point marked on the disk.
The person's angular speed is
v/r = (2.00 m/s) / (1.25 m) = 1.6 rad/s
As the person and the disk are moving in opposite directions, the person will run part of a revolution and the turning disk would complete the whole revolution.
(angle) + (angle disk turns) = 2π
(1.6 rad/s)(t) + ωt = 2π
t[1.6 rad/s + 1 rad/s] = 2π
t = 2.41 s
<span>Standard deviation is a calculation. It I used in statistical analysis of a easier job. hoped this helps u </span>
