All categories

2 years ago

Lora (of mass 47.4 kg) is an expert skier. She

Physics

1 answer:

Harrizon [31]2 years ago

6 0

Answer:

Kinetic energy is 242.7 Joule

Explanation:

m = 47.4 kg

v = 3.2m/s²

Now,

K.E. = 1/2 × m × v²

or, K.E. = 1/2 × 47.4 × 3.2²

or, K.E. = 242.7 Joule

You might be interested in

A ball tied on a string rotates in a circular path as shown above. The only forces acting on the ball at any point are the weigh

Harlamova29_29 [7]

Answer:

the third one T-W

Explanation:

the direction of the Tension and weight are opposite

6 0

2 years ago

[1] The assembly starts from rest and reaches an angular speed of 150 rev/min under the action of a 20-N force T applied to the

ExtremeBDS [4]

Answer:

t = 5.89 s

Explanation:

To calculate the time, we need the radius of the pulley and the radius of the sphere which was not given in the question.

Let us assume that the radius of the pulley ( $r_p$ ) = 0.4 m

Let the radius of the sphere (r) = 0.5 m

w = angular speed = 150 rev/min = (150 × 2π / 60) rad/s = 15.708 rad/s

Tension (T) = 20 N

mass (m) = 3 kg each

$\int\limits^0_t {Tr_p} \, dt=H_2-H_1\\( Tr_p)t=4rm(rw)\\( Tr_p)t=4r^2mw$

$t = \frac{4r^2mw}{Tr_P}$

Substituting values:

$t = \frac{4r^2mw}{Tr_P}= \frac{4*(0.5)^2*3*15.708}{20*0.4}=5.89s$

7 0

3 years ago

Read 2 more answers

Of all the planets, which is the most different from the others? Explain.

Alenkinab [10]

Answer: VENUS

Explanation:

Venus tiene una lenta rotación retrógrada, lo que significa que gira de este a oeste, en lugar de hacerlo de oeste a este como lo hacen la mayoría de los demás planetas mayores (Urano también tiene una rotación retrógrada, aunque el eje de rotación de Urano, inclinado 97.86°, prácticamente descansa sobre el plano.

5 0

3 years ago

Read 2 more answers

Two coherent sources of radio waves, A and B, are 5.00 meters apart. Each source emits waves with wavelength 6.00 meters. Consid

Korolek [52]

Answer:

$z= 2.5 \ m$

$z = (1 \ m , 4 \ m )$

Explanation:

From the question we are told that

Their distance apart is $d = 5.00 \ m$

The wavelength of each source wave $\lambda = 6.0 \ m$

Let the distance from source A where the construct interference occurred be z

Generally the path difference for constructive interference is

$z - (d-z) = m \lambda$

Now given that we are considering just the straight line (i.e points along the line connecting the two sources ) then the order of the maxima m = 0

$z - (5-z) = 0$

=> $2 z - 5 = 0$

=> $z= 2.5 \ m$

Generally the path difference for destructive interference is

$|z-(d-z)| = (2m + 1)\frac{\lambda}{2}$

=> $|2z - d |= (0 + 1)\frac{\lambda}{2}$

=> $|2z - d| =\frac{\lambda}{2}$

substituting values

$|2z - 5| =\frac{6}{2}$

=> $z = \frac{5 \pm 3}{2}$

$z = \frac{5 + 3}{2}$

$z = 4\ m$

and

$z = \frac{ 5 -3 }{2}$

=> $z = 1 \ m$

=> $z = (1 \ m , 4 \ m )$

7 0

3 years ago

which element is less reactive, an element whose atoms have seven valence electrons or an element whose atoms have eight valence

Agata [3.3K]

Which element is less reactive, an element whose atoms have seven valence electrons or an element whose atoms have eight valence electrons? Why?<span>an element with 8 valence electrons because it doesn't require any additional electrons to become stable</span>

5 0

3 years ago