Many animals rely on their sense to alert them about changes in temperature. <span>Some ways that animals adapt for the seasons include migration, hibernation and physical changes that help them survive the differences in the weather. Hope this helps.</span>
Answer:
B. I, III and IV
Explanation:
The strength of the magnetic field generated by a solenoid is given by the following formula:
B = μ₀NI/L
where,
B = Magnetic Field
μ₀ = Permeability of Free Space
N = No. of Coils
I = Current Magnitude
L = Length of Coil
Strength is also directly proportional to size of the core.
So, to increase the magnetic field strength we can:
1- The number of Loops
2- Increase the amount of Current (for same length)
3- Decrease the length (for same number of loops)
4- Increase Size of Core
So, the correct answer is:
<u>B. I, III and IV</u>
Reflection is when light bounces off an object. If the surface is smooth and shiny, like glass, water or polished metal, the light will reflect at the same angle as it hit the surface. This is called specular reflection. Light reflects from a smooth surface at the same angle as it hits the surface
Downward movement under the force of gravity only.
Answer:
y = 2.74 m
Explanation:
The linear thermal expansion processes are described by the expression
ΔL = α L ΔT
Where α the thermal dilation constant for concrete is 12 10⁻⁶ºC⁻¹, ΔL is the length variation and ΔT the temperature variation in this case 20ªc
If the bridge is 250 m long and is covered by two sections each of them must be L = 125 m, let's calculate the variation in length
ΔL = 12 10⁻⁶ 125 20
ΔL = 3.0 10⁻² m
Let's use trigonometry to find the height
The hypotenuse Lf = 125 + 0.03 = 125.03 m
Adjacent leg L₀ = 125 m
cos θ = L₀ / Lf
θ = cos⁻¹ (L₀ / Lf)
θ = cos⁻¹ (125 / 125.03)
θ = 1,255º
We calculate the height
tan 1,255 = y / x
y = x tan 1,255
y = 125 tan 1,255
y = 2.74 m