Refer to the diagram shown below.
At A, the boy begins walking up the stairs.
At B, the boy is at the top of the slide. He has acquired PE (potential energy).
The value of the PE is
(50 kg)*(9.8 m/s²)*(11.5 m) = 5635 J
At C, the boy has KE (kinetic energy).
The value of the KE is
(1/2)*(50 kg)*(12 m/s)² = 3600 J
Energy is lost between B and C due to friction.
The lost energy is
5635 - 3600 = 2035 J
The distance traveled along the slide is 108 m.
If F = the average frictional force, then
(F N)*(108 m) = 2035 J
F = 18.84 N
Answers:
(a) The mechanical energy lost by sliding is 2035 J.
(b) The average frictional force is 18.84 N
Answer:
D. 200 kgm/s
Explanation:
Momentum is conserved.
Initial momentum = final momentum
(50 kg) (4 m/s) + (30 kg) (0 m/s) = final momentum
200 kgm/s = final momentum
(198,000 joule / 15 minute) x (minute / 60 sec) = 220 joule/sec = <em>220 watts
</em>
Answer:
The frequency of the infrared light is approximately 3.156 × 10¹⁴ Hz
Explanation:
Given that the wavelength of infrared light, λ = 9.50 × 10⁻⁷ m, we have;
The speed of light (which is constant), c = v × λ = 299,792,458 m
Where v = The frequency of the infrared light, we have;
v = c/λ = 299,792,458/(9.50 × 10⁻⁷) ≈ 3.156 × 10¹⁴ Hz
The frequency of the infrared light = v ≈ 3.156 × 10¹⁴ Hz.
The answer is C because its shiny