Answer:
T= 19.74 N
Explanation:
The tension in the string will be equal to centripetal force on the ball. (Newton's 3rd law, equal acting and reacting forces acts on a body)
T = Fc
Fc = m w ²r
here:
m = 0.25 kg, r = 0.5 m
w = 2 rps = 2 * 2π rad/s ( ∴ 1 revolution = 2π radians )
w = 4π rad/s
Fc = m w ²r = 0.25 * ( 4π )² * 0.5 N
Fc = T = 19.74 N
T= 19.74 N
Use force (thrust) equals mass times acceleration.
Answer:<span>Humid air is lighter, so it has lower pressure.
The reason is the molecules of water are H2O, whose molar mass is 18 g/mol.
These molecules displaces molecules of N2 and O2, whose molar masses are:
N2: 2*14g/mol = 28 g/mol, and
O2: 2*16g/mol = 32 g/mol.
Then molecules of 28g/mol and 32 g/mol are being replaced with molecules of 18g/mol, leading to a lower weight of the same volume of air, which results in lower pressure.
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Answer:
a)
b)
Explanation:
Searching the missed information we have:
E: is the energy emitted in the plutonium decay = 8.40x10⁻¹³ J
m(⁴He): is the mass of the helium nucleus = 6.68x10⁻²⁷ kg
m(²³⁵U): is the mass of the helium U-235 nucleus = 3.92x10⁻²⁵ kg
a) We can find the velocities of the two nuclei by conservation of linear momentum and kinetic energy:
Linear momentum:
Since the plutonium nucleus is originally at rest, :
(1)
Kinetic Energy:
(2)
By entering equation (1) into (2) we have:
Solving the above equation for we have:
And by entering that value into equation (1):
The minus sign means that the helium-4 nucleus is moving in the opposite direction to the uranium-235 nucleus.
b) Now, the kinetic energy of each nucleus is:
For He-4:
For U-235:
I hope it helps you!