The acceleration of the car with two washers added to the string would be what?

A 68 kg hiker walks at 5.0 km/h up a 9% slope. The indicated incline is the ratio of the vertical distance and the horizontal di

Softa [913]

The formula used to calculate power is:

Power = Work / Time

Where Work is defined as Force multiplied by Distance, hence:

Power = Force * Distance / Time

This can also be expressed as:

Power = Force * Velocity

Converting the velocity from km/h to m/s:

Velocity = (5 km / h) (1000 m / km) (1 h / 3600 s)
Velocity = 1.39 m/s

The calculated force corresponds to the vertical component of the hiker's weight:

Force = Wy * g = W * sin θ * g

To find the angle θ, we utilize the slope, which is defined as:

slope = tan θ = ratio of vertical to horizontal distance

tan θ = 0.09

θ = 5.14˚

Thus, we have Force = 68 kg * sin(5.14˚) * 9.8 m/s²
Force = 666.4 * sin(5.14) = 59.73 N

Now, let's compute the power:
Power = 59.73 N * 1.39 m/s = 82.96 W
Given the hiker's efficiency is at 25%, we can find the metabolic power:
Metabolic Power = 82.96 W / 0.25 = 331.83 watts

6 0

2 days ago

Phyllis had always been the one to take care of Douglas, now he feels as if it is his duty and privilege to take care of her, ev

ValentinkaMS [1144]

1. Certainty in Reasoning: Douglas is confident in his ability to reason well to make sound judgments.

2. Analytical: Douglas remains constantly aware of potential issues and is proactive in predicting both short-term and long-term consequences while taking care of his wife.

7 0

2 days ago

Read 2 more answers

The magnitude of the Poynting vector of a planar electromagnetic wave has an average value of 0.939 W/m2. The wave is incident u

Yuliya22 [1153]

Answer:

The total energy can be expressed as $T = 169.02 \ J$

Explanation:

The problem states that

The Poynting vector, which measures energy flux, equals $k = 0.939 \ W/m^2$

The rectangle's length is represented by $l = 1.5 \ m$

The width of the rectangle is $w = 2.0 \ m$

The duration considered is $t = 1 \ minute = 60 \ s$

Mathematically, the overall electromagnetic energy incident on the area is given by

$T = k * A * t$

where A denotes the area of the rectangle, calculated as

$A= l * w$

By plugging in the respective values

$A= 2 * 1.5$

$A= 3 \ m^2$

Again substituting values

$T = 0.939 * 3 * 60$

$T = 169.02 \ J$

5 0

6 days ago

A new roller coaster contains a loop-the-loop in which the car and rider are completely upside down. If the radius of the loop i

Sav [1095]

Respuesta:

11.4 m/s

Explicación:

La fórmula para la aceleración centrípeta es:

$a=\frac{v^2}{R}$

donde, a es la aceleración, v la velocidad alrededor de la circunferencia y R el radio del círculo.

En este problema,

a = g = aceleración debida a la gravedad en la cima = $9.81\ m/s^2$

v = ?

R = 13.2 m

Por lo tanto,

$9.81=\frac{v^2}{13.2}$

$v^2=9.81\times {13.2}$

v = 11.4 m/s

8 0

13 days ago

1)After catching the ball, Sarah throws it back to Julie. However, Sarah throws it too hard so it is over Julie's head when it r

Softa [913]

Answer:

1)

$v_{oy}=11.29\ m/s$

2)

$y=7.39\ m$

Explanation:

Projectile Motion

When an object is projected near the surface of the Earth at an angle $\theta$ to the horizontal, it follows a trajectory known as a parabola. The only force acting on it (ignoring wind resistance) is gravity, affecting the vertical axis.