Prima problema este urgent

Which EM wave is about the size of humans?

shutvik [7]

The Electromagnetic ave that is about the size of humans is : A typical micro waves have around 14 inches ( 1.1 meter) in height.
This is very similar to the height of human right before we hit puberty (around 9 - 10 years old)

8 0

3 years ago

Dragsters can actually reach a top speed of 145.0 m/s in only 4.45 s. (a) Calculate the average acceleration for such a dragster

astraxan [27]

Answer:

a) 32.58 m/s²

b) 161.84 m/s

Explanation:

Initial velocity = u = 0

Final velocity = v = 145 m/s

Time taken = t = 4.45 s

s = Displacement of dragster = 402 m

a = Acceleration

$v=u+at\\\Rightarrow a=\frac{v-u}{t}\\\Rightarrow a=\frac{145-0}{4.45}\\\Rightarrow a=32.58\ m/s^2$

$v^2-u^2=2as\\\Rightarrow v=\sqrt{2as-u^2}\\\Rightarrow v=\sqrt{2\times 32.58\times 402-0^2}\\\Rightarrow v=161.84\ m/s$

The final velocity is greater than the velocity used to find the average acceleration due to the gear changes. The first gear in a dragster has the most amount of toque which means the acceleration will be maximum. The final gears have less torque which means the acceleration is lower here. The final gears have less acceleration but can spin faster which makes the dragster able to reach higher speeds but slowly.

7 0

2 years ago

The flatbed truck is traveling at the constant speed of 60 km/h up the 15‐percent grade when the 100‐kg crate which it carries i

Alexus [3.1K]

Answer:

μ = 0.309

Explanation:

coefficient of kinetic friction is defined as the ratio of two forces, friction force and the normal force acting on the object.

θ = arctan(15/100)= 8.531⁰

In the vertical direction:

N = mgcosθ = 100 *9.8 *cos(8.531) = 970N

law of conservation of energy implies

mgsinθ - μNx = 1/2m(v₂²-v₁²)

100*9.8*sin (8.531) - μ(970*2) = 1/2(100)(0²-3²)

150.6 - 1940μ = 450

- 1940μ = -600.6

μ = 0.309

7 0

2 years ago

Is the water the same temperature in alaska and mexico?

Snezhnost [94]

Colder in Alaska, warmer in Mexico.

6 0

3 years ago

Three parallel wires each carry current I in the directions shown in (Figure 1). The separation between adjacent wires is d.

jasenka [17]

(a) The magnitude of the net magnetic force per unit length on the top wire is μI²/πd.

(b) The magnitude of the net magnetic force per unit length on the middle wire is zero.

(c) The magnitude of the net magnetic force per unit length on the bottom wire is 3μI²/4πd.

<h3>Force per unit length</h3>

The magnitude of the net magnetic force per unit length on the top wire is calculated as follows;

F₁/L = (μI₁/2π) x (I₂/d + I₃/d)

F₁/L = (μI/2π) x (I/d + I/d)

F₁/L = (μI/2π) x (2I/d)

F₁/L = μI²/πd

The magnitude of the net magnetic force per unit length on the middle wire is calculated as follows;

F₂/L = (μI₂/2π) x (I₃/d - I₁/d)

F₂/L = (μI/2π) x (I/d - I/d) = 0

The magnitude of the net magnetic force per unit length on the middle bottom is calculated as follows;

F₃/L = (μI₂/2π) x (I₁/d + I₂/d)

F₃/L = (μI/2π) x (I/2d + I/d)

F₃/L = (μI/2π) x (3I/2d)

F₃/L = 3μI²/4πd

Thus, the magnitude of the net magnetic force per unit length on the top wire is μI²/πd.

The magnitude of the net magnetic force per unit length on the middle wire is zero.

The magnitude of the net magnetic force per unit length on the bottom wire is 3μI²/4πd.

Learn more about magnetic force here: brainly.com/question/13277365

#SPJ1

6 0

1 year ago