For this case we first think that the skateboard and the child are one body.
We have then:
1 = jug
2 = skateboard + boy
By conservation of the linear amount of movement:
M1V1i + M2V2i = M1V1f + M2V2f
Initial rest:
v1i = v2i = 0
0 = M1V1f + M2V2f
Substituting values
0 = (7.8) (3.2) + (M2) (- 0.65)
0 = 24.96 + M2 (-0.65)
-24.96 = (-0.65) M2
M2 = (-24.96) / (- 0.65) = 38.4 kg
Then, the child's mass is:
M2 = Mskateboard + Mb
Clearing:
Mb = M2-Mskateboard
Mb = 38.4 - 1.9
Mb = 36.5 Kg
answer:
the boy's mass is 36.5 Kg
Ok so here is the thing. It is necessary to introduce the atomic number Z into the following equation and the reason for that is that we are not working here with hydrogen (H). It will go like this:
<span>E=(2.18×10^-18 J)(Z^2 )|1/(ni^2 )-1/(nf^2 )| </span>
<span>E=(2.18×10^-18 J)(2^2 )|1/(6 ^2 )-1/(4 ^2 )|=3.02798×10^-19 J </span>
<span>After that we need to plug the E value calculated into the equation. Remember that the wavelength is always positive:</span>
<span>E=hc/λ 3.02798×10^-19 J=hc/λ λ=6.56×10^-7 m </span>
so 6.56×10^-7 m or better written 656 nm is in the visible spectrum
Answer:
Jolt can expect to replace 160 units.
Explanation:
given data:
standard deviation 1.7
average lfe of connectors = 18.2 months
number of connectors = 5000
z(19) = 0.4706
P(x< 19) = P(z< 0.4706)
P(x< 19) = 0.6810 from z table
therefore 68.1% fails within 19 months.
hence 0.3190 {100-68.1} will fail during that period.
number of unit of Jolt that need to be replace, on average is 0.319*500 = 160 units.
72 m/s
Explanation:
Given,
Frequency ( f ) = 6 Hz
Wavelength ( λ ) = 12 m
To find : -
Speed ( v ) = ?
Formula : -
v = f x λ
v
= 6 x 12
= 72 m/s
Therefore,
the speed of a wave with a frequency of 6 Hz and a wavelength of 12 m is 72 m/s.
