Yes, electromagnetic waves do carry energy. In fact, every wave carries energy: that is, potential energy.
Answer:
769,048.28Joules
Explanation:
A parachutist of mass 56.0 kg jumps out of a balloon at a height of 1400 m and lands on the ground with a speed of 5.10 m/s. How much energy was lost to air friction during this bump
The energy lost due to friction is expressed using the formula;
Energy lost = Potential Energy + Kinetic Energy
Energy lost = mgh + 1/2mv²
m is the mass
g is the acceleration due to gravity
h is the height
v is the speed
Substitute the given values into the formula;
Energy lost = 56(9.8)(1400) + 1/2(56)(5.10)²
Energy lost = 768,320 + 728.28
Energy lost = 769,048.28Joules
<em>Hence the amount of energy that was lost to air friction during this jump is 769,048.28Joules</em>
Answer:
Pressure, 
Explanation:
It is given that,
Combined mass of the man and the chair, m = 95 kg
Radius of the leg of chair, r = 0.5 cm = 0.005 m
A large man sits on a four-legged chair with his feet off the floor. The force acting per unit area is called the pressure exerted.
Area of 4 legs, A = 4 A
So, the pressure each leg exert on the floor is 
. Hence, this is the required solution.
Answer:
a = v^2/r centripetal acceleration
v = (a * r)^1/2 = (42 * .23)^1/2 = 3.1 m/s
Answer:
a) α = 0.338 rad / s² b) θ = 21.9 rev
Explanation:
a) To solve this exercise we will use Newton's second law for rotational movement, that is, torque
τ = I α
fr r = I α
Now we write the translational Newton equation in the radial direction
N- F = 0
N = F
The friction force equation is
fr = μ N
fr = μ F
The moment of inertia of a saying is
I = ½ m r²
Let's replace in the torque equation
(μ F) r = (½ m r²) α
α = 2 μ F / (m r)
α = 2 0.2 24 / (86 0.33)
α = 0.338 rad / s²
b) let's use the relationship of rotational kinematics
w² = w₀² - 2 α θ
0 = w₀² - 2 α θ
θ = w₀² / 2 α
Let's reduce the angular velocity
w₀ = 92 rpm (2π rad / 1 rev) (1 min / 60s) = 9.634 rad / s
θ = 9.634 2 / (2 0.338)
θ = 137.3 rad
Let's reduce radians to revolutions
θ = 137.3 rad (1 rev / 2π rad)
θ = 21.9 rev
