Ask question

Ask question

All categories

4 years ago

8

A4 40 kg girl skates at 3.5 m/s one ice toward her 65 kg friend who is standing still, with open arms. As they collide and hold

each other, what is the speed of the couple?

1 answer:

salantis [7]4 years ago

8 0

Explanation:

Below is an attachment containing the solution.

You might be interested in

As a skateboarder moves downhill, some of the energy of the skateboarder is

Sonja [21]

As the skateboard rolls down the ramp it loses potential energy and gains kinetic energy.

6 0

3 years ago

Read 2 more answers

A sinusoidal sound wave moves through a medium and is described by the displacement wave function

labwork [276]

By applying the wave equation we know that the displacement on the y-axis is 1.999 micrometers.

We need to know about wave equations to solve this problem. The displacement of the wave on the y-axis can be explained by the wave equation

y = A cos (kx - ωt)

where y is y-axis displacement, A is amplitude, k is wave number, x is x-axis displacement, ω is angular speed and t is time.

the wavenumber and angular speed of the wave equation can be determined respectively by

k = 2π / λ

ω = 2πf

where k is the wavenumber, λ is wavelength and f is frequency.

From the question above, we know that:

y = 2.00cos (15.7x - 858t)

(x in meters, t in second, y in micrometers)

x = 0.05 m

t = 3 ms

Convert time to second

t = 3ms = 0.003 s

By applying the wave equation, we get

y = 2.00cos (15.7x - 858t)

y = 2.00cos (15.7(0.05) - 858(0.003))

y = 2 cos(-1.789)

y = 1.999 micrometers

For more on wave equation on: brainly.com/question/25699025

#SPJ4

7 0

2 years ago

A boxer punches a sheet of paper in midair and brings it from rest up to a speed of 30 m/s in 0.060 s .

zimovet [89]

Answer:

Force exerted, F = 1.5 N

Explanation:

It is given that, a boxer punches a sheet of paper in midair and brings it from rest up to a speed of 30 m/s in 0.060 s.

i.e. u = 0

v = 30 m/s

Time taken, t = 0.06 s

Mass of the paper, m = 0.003 kg

We need to find the force the boxer exert on it. The force can be calculated using second law of motion as :

$F=m\times a$

$F=m\times (\dfrac{v-u}{t})$

$F=0.003\times (\dfrac{30}{0.06})$

F = 1.5 N

So, the force the boxer exert on the paper is 1.5 N. Hence, this is the required solution.

6 0

3 years ago

Suppose you increase your walking speed from 7 m/s to 15 m/s in a period of 3 s. What is your acceleration?

lisov135 [29]

You asked the question twice I answered it on the last one

7 0

4 years ago

Assuming a typical efficiency for energy use by the body, how many slices of pizza must you eat to walk for 2.5 h at a speed of

larisa86 [58]

Answer:

2.7 Pizzas.

Explanation:

The power required to walk through 5km in 1 hour is 380W.

A watt is basically Jules per second, then we need to standardized this measurement to second.

5km/hr is equal to,

$\frac{5km}{hr}*\frac{1hr}{3600s}*\frac{1000m}{1km}=1.389m/s$

Walking by 2.5 hours is equal to a distance of,

$d=v*t=1.389*(2.5*3600) = 12500m$

The total energy required then would be,

$E = \frac{380J}{1.389m/s}(12500)=3.4199*10^6J$

Then we know that one pizza slice gives $1260*10^3J$ of energy, the total pizza needed are,

$\eta = \frac{3.4199*10^6}{1260*10^3} = 2.7142$

<em>Then you need to buy 3 pizza.</em>

6 0

4 years ago