PHYSICAL CHANGES :
Melting an ice cube.
Boiling water.
Mixing sand and water.
Breaking a glass.
CHEMICAL CHANGES :
Digesting food.
Cooking an egg.
Heating sugar to form caramel.
Answer:
10.52 m
Explanation:
The power radiated by a body is given by
P = σεAT⁴ where ε = emissivity = 0.97, T = temperature = 30 C + 273 = 303 K, A = surface area of human body = 1.8 m², σ = 5.67 × 10⁻⁴ W/m²K⁴
P = σεAT⁴ = 5.67 × 10⁻⁸ W/m²K⁴ × 0.97 × 1.8 m² × (303)⁴ = 834.45 W
This is the power radiated by the human body.
The intensity I = P/A where A = 4πr² where r = distance from human body.
I = P/4πr²
r = (√P/πI)/2
If the python is able to detect an intensity of 0.60 W/m², with a power of 834.45 W emitted by the human body, the maximum distance r, is thus
r = (√P/πI)/2 = (√834.45/0.60π)/2 = 21.04/2 = 10.52 m
So, the maximum distance at which a python could detect your presence is 10.52 m.
Answer:
The solution is attached in the pictures below
Explanation:
Answer:
μ = mg/kx
Explanation:
Since the bock does not slip, the frictional force equals the weight of the block. So, F = mg. Now, the frictional force, F = μN where μ = coefficient of static friction and N = Normal force.
Now, the normal force equals the spring force F' = kx where k = spring constant and x = compression of spring.
N = F' = kx
So, F = μN = μkx
μkx = mg
So, μ = mg/kx
<u>Answer:</u>
Force = 20N
acceleration (a) = 1.5 m/s²
Mass of object (m) = ?
<u>From Newtons II law</u>
<em> F = m. a N</em>
m = F/a
m = 20/1.5
<em> m = 13.34 Kg</em>
<em>Mass of an object is 13.34 Kg</em>
