Answer:
0.358g
Explanation:
Density of Helium = 0.179g/L
ρ=m/v
m=ρv
when the volume was 2L
m1= 0.179*2
m1=0.358g
when the volume increased to 4L
m2= 0.179*4
m2=0.716g
gram of helium added = 0.716g-0.358g
=0.358g
The rms speed can be calculated using the following rule:
rms = sqrt ((3RT) / (M)) where:
R is the gas constant = 8.314 J/mol-K
T is the temperature = 31.5 + 273 = 304.5 degrees kelvin
M is the molar mass = 2*14 = 28 grams = 0.028 kg
Substitute with the givens to get the rms speed as follows:
rms speed = sqrt [(3*8.314*304.5) / (0.028)] = 520.811 m/sec
Answer:
86.6, 45°
Explanation:
The diagram explains better.
Using vector component method:
We find the x and y components of the vectors :
For the first:
A = -50cos(0)i + 50sin(0)j
A = -50i
For the second:
B = -50cos(60)i + 50sin(60)j
B = -25i + 43.3j
The resultant vector is :
R = A + B
R = -50i - 25i + 43.3j
R = -75i + 43.3j
The magnitude is:
R = [(-75)² + (43.3)²]^½
R = 86.6m
The angle is
tanθ = (50/50) = 1
θ = 45°