Answer:
Visible light has a shorter wavelength than radio waves
Answer:
v = 3.7 m/s
Explanation:
As the swing starts from rest, if we choose the lowest point of the trajectory to be the zero reference level for gravitational potential energy, and if we neglect air resistance, we can apply energy conservation as follows:
m. g. h = 1/2 m v²
The only unknown (let alone the speed) in the equation , is the height from which the swing is released.
At this point, the ropes make a 30⁰ angle with the vertical, so we can obtain the vertical length at this point as L cos 30⁰, appying simply cos definition.
As the height we are looking for is the difference respect from the vertical length L, we can simply write as follows:
h = L - Lcos 30⁰ = 5m -5m. 0.866 = 4.3 m
Replacing in the energy conservation equation, and solving for v, we get:
v = √2.g.(L-Lcos30⁰) = √2.9.8 m/s². 4.3 m =3.7 m/s
Answer;
Mechanical control
Explanation;
-Invasive species may cause environmental harm, economic harm, or impact human health. A key factor that makes many species invasive is a lack of predators in the new environment.
-Mechanical control usually refers to the mowing or mechanical cutting of an invasive plant infestation to limit seed production. With mowing, timing is essential. Invasive plants must be removed before the plants go to seed in order to be an effective method of control. Plants should be cut as close to the ground as possible and may have to be treated more than once in a growing season to achieve desired results.
Answer:
7.75 s
Explanation:
Newton's second law:
∑F = ma
35 N = (70 kg) a
a = 0.5 m/s²
Given v₀ = 0 m/s and Δx = 15 m:
Δx = v₀ t + ½ at²
(15 m) = (0 m/s) t + ½ (0.5 m/s²) t²
t = 7.75 s
