Answer:
She is going at 30.4 m/s at the top of the 35-meter hill.
Explanation:
We can find the velocity of the skier by energy conservation:
On the top of the hill 1 (h₁), she has only potential energy since she starts from rest. Now, on the top of the hill 2 (h₂), she has potential energy and kinetic energy.
(1)
Where:
m: is the mass of the skier
h₁: is the height 1 = 82 m
h₂: is the height 2 = 35 m
g: is the acceleration due to gravity = 9.81 m/s²
v₂: is the speed of the skier at the top of h₂ =?
Now, by solving equation (1) for v₂ we have:
Therefore, she is going at 30.4 m/s at the top of the 35-meter hill.
I hope it helps you!
Answer:
18 L
Explanation:
Use ideal gas law:
PV = nRT
Find initial number of moles, but first convert to units that match the gas constant units.
(200,000 Pa) (0.025 m³) = n (8.314 Pa m³ / mol / K) (25 + 273.15 K)
n = 2.017 mol
At the new pressure and temperature:
(250,000 Pa) V = (2.017 mol) (8.314 Pa m³ / mol / K) (0 + 273.15 K)
V = 0.018 m³
V = 18 L
Answer:
Explanation:
Q1 = +2.50 x 10^-5C and Q2 = -2.50 x 10^-5C, r = 0.50m, F=?
Using Coulomb's law:
F = 1/(4πE) x Q1 x Q2/ r^2
Where
k= 1/(4πE) = 9 x 10^9Nm2/C2
Therefore,
F = 9x 10^9 x 2.50 x 10^-5 x2.50 x
10^-5/. ( 0.5)^2
F= 5.625/ 0.25
F= 22.5N approximately
F= 23N.
To find the direction of the force: since Q1 is positive and Q2 is negative, the force along Q1 and Q2 is force of attraction.
Hence To = 23N, attractive. C ans.
Thanks.
The relationship between wavelength (λ), frequency (f), and speed (c), is given by
So the wavelength here is
Answer:
10%
Explanation:
Efficiency = work done / energy used
e = (10 m × 100 N) / (10,000 J)
e = 0.1
The efficiency is 0.1, or 10%.
