Answer:2.21 x 10^-7 m
Explanation:
From the question we know that,
Phi = 9.05 x 10^-19 J
Now with Vo being the threshold frequency and h being Plancks constant, then the threshold (i.e. MINIMUM) frequency required to ionize the metal is:
Vo = 9.05 x 10^-19 / 6.626 x 10^34 J.s
= 1.36 x 10^15 s^1
The MAXIMUM wavelength this corresponds to is
Landa = C / Vo = 3 x 10^8 / 1.36 x 10^15
Wavelength = 2.21 x 10^-7m
= 2.21 x 10^-7 nm
More work was done in the skateboard that came to a stop because the one that rolled across the room moved on a surface with less friction while the second board used more work to move on a surface with much friction.
Answer:
500000N/m²
5250N
Explanation:
Given parameters:
Depth(H) = 50m
Density of water = 1000kg/m³
Acceleration of free fall = 10m/s
Unknown:
Pressure the water exerts on the diver = ?
Solution:
Pressure is the force per unit area on a body. In fluids, pressure is the product of density, gravity and height
Pressure in fluids = Density x acceleration due to gravity x height
Input the variables and solve;
Pressure in fluids = 1000 x 10 x 50 = 500000N/m²
B.
width of window = 150mm
height of window = 70mm
Force water exerts on the window = ?
To solve this problem;
Pressure =
Area of the window = width x height = 150 x 10⁻³ x 70 x 10⁻³
= 1.05 x 10 ⁻²m²
Force = pressure x area
Input the variables;
= 500000N/m² x 1.05 x 10 ⁻²m²
= 5250N
First answer: vibrations Second: louder
Answer:
Explanation:
distance travelled
s = 2πR
= 2 X 3.14 X 140
= 880 m
final velocity = v
initial velocity = u
distance travelled = s
time = 60 s
s = ut + 1/2 at²
880 = .5 x a x 60²
a = .244 m/s²
final velocity v = at
= .244 x 60
= 14.66
centripetal acceleration at final moment
v² /R
14.66 X 14.66 / 140
= 1.53 m/s⁻²
1.53 m/s²
this is centripetal acceleration which acts towards the centre.
tangential acceleration calculated a _t = .244
redial acceleration ( centripetal ) = 1.53
Resultant acceleration
R²= 1.53² + .244 ²
R = 1.55 m/s²
total force = 1.55 x 76
= 118 N