The properties of minerals that might help Jimmy and his partners to identify the sample other than Hardness (scratch test) are:
1. Color
2. Crystalline Structure
3. Cleavage or Fracture
4. Transparency
5. Tenacity
Answer:
solution given:
acceleration (a)=?
initial velocity (u)=3m/s
final velocity (v)=6m/s
distance (s)=90m
we have
v²=u²+2as
substituting value
6²=3²+2*a*90
36=9+180a
36-9=180a
a=25/180
<u>a=0.1388m/s²</u>
When light travels from a medium with higher refractive index into a medium with lower refractive index, there is a maximum angle (called critical angle) for which all the light is reflected, so there is no refraction.
The value of the critical angle is given by:

when n1 is the refractive index of the first medium, while n2 is the refractive index of the second medium. In our case, n1=1.33 (the water) and n1=1.00 (the air). Putting numbers in, we get
Force= mass x acceleration
79=mass(3)
m=79/3
m=26.3 kg