Answer:
The force required to begin to lift the pole from the end 'A' is 240 N
Explanation:
The given parameters for the pole AB are;
The length of the pole, l = 10.0 m
The weight of the pole, W = 600 N ↓
The distance of the center of gravity of the pole from the side 'A' = 4.0 m
Let '
' represent the force required to begin to lift the pole from the end 'A' and let a force applied in the upwards direction be positive
For equilibrium, the sum of moment about the point 'B' = 0, therefore, taking moment about 'B', we have
× 10.0 m - W × 4.0 m = 0
∴
× 10.0 m = W × 4.0 m = 600 N × 4.0 m
× 10.0 m = 600 N × 4.0 m
∴
= 600 N × 4.0 m/(10.0 m) = 240 N
The force required to begin to lift the pole from the end 'A',
= 240 N.
Food has calories which feeds your bones in your body from eating away your muscles, it doesn’t have “energy” on the other hand pop and drinks do.
2.8 kg .............is the mass of a 1.2 N book.
Answer:
C
Explanation:
During investigations a scientist needs to observe, investigate, collect data and put together the information they collect.
Answer:
(a) λ = 4136 nm → infrared
(b) λ = 413.6 nm → visible light
(c) λ = 41.36 nm → ultraviolet
Explanation:
The wavelength of infrared is on the range of 700 nm to 1000000 nm
The wavelength of visible light is between 400 nm and 700 nm
The wavelength of ultraviolet ray on the range of 10 nm to 400 nm
The wavelength of photon is given by;
E = hf
f is the frequency of the wave = c / λ

Where;
c is the speed of light = 3 x 10⁸ m/s
h is Planck's constant = 6.626 x 10⁻³⁴ J/s
(a) 0.3 eV = 0.3 x 1.602 x 10⁻¹⁹ J

λ = 4136 x 10⁻⁹ m
λ = 4136 nm → infrared
(b) 3.0 eV

λ = 413.6 x 10⁻⁹ m
λ = 413.6 nm →visible light
(c) 30 eV

λ = 41.36 x 10⁻⁹ m
λ = 41.36 nm →ultraviolet