Mark Brainliest please
Friction is a nonconservative force. Therefore work done against friction cannot be stored as potential energy and later converted back to kinetic the way work against gravity can.
Gravity always pulls objects such as a desk, book or person down. Thus, when you jump, gravity causes you to land on the ground. Friction, however, doesn't pull objects down. ... Instead friction occurs when something like a machine or individual pulls a sliding object in the opposite direction of another object.
Friction and gravity exist in every aspect of a person’s life. For example, almost every movement you make, such as walking and running, involves friction. When you throw a ball up, gravity causes the ball to fall down. A person sliding a book across a table creates friction. Nevertheless, differences between gravity and friction also exist. Force affects gravity and friction in different ways.
Answer:
4.42 x 10⁷ W/m²
Explanation:
A = energy absorbed = 500 J
η = efficiency = 0.90
E = Total energy
Total energy is given as
E = A/η
E = 500/0.90
E = 555.55 J
t = time = 4.00 s
Power of the beam is given as
P = E /t
P = 555.55/4.00
P = 138.88 Watt
d = diameter of the circular spot = 2.00 mm = 2 x 10⁻³ m
Area of the circular spot is given as
A = (0.25) πd²
A = (0.25) (3.14) (2 x 10⁻³)²
A = 3.14 x 10⁻⁶ m²
Intensity of the beam is given as
I = P /A
I = 138.88 / (3.14 x 10⁻⁶)
I = 4.42 x 10⁷ W/m²
energy associate with position or shape
C.half the energy is carried by the electric field and half is carried by the magnetic field.
Answer:
0.74 N/cm
Explanation:
The following data were obtained from the question:
Mass (m) = 3 Kg
Extention (e) = 40 cm
Spring constant (K) =?
Next, we shall determine the force exerted on the spring.
This can be obtained as follow:
Mass (m) = 3 Kg
Acceleration due to gravity (g) = 9.8 m/s²
Force (F) =?
F = mg
F = 3 × 9.8
F = 29.4 N
Finally, we shall determine the spring constant of the spring. This can be obtained as follow:
Extention (e) = 40 cm
Force (F) = 29.4 N
Spring constant (K) =?
F = Ke
29.4 = K × 40
Divide both side by 40
K = 29.4 / 40
K = 0.74 N/cm
Therefore, the spring constant of the spring is 0.74 N/cm
