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2 years ago

Amy uses 20 N of force to push a lawnmower 10 meters. How much work does she do?

Physics

1 answer:

Ira Lisetskai [31]2 years ago

8 0

Answer:

200J

Explanation:

work done = force x distance

= 20 x 10

= 200J

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During a storm, the waves at this lighthouse were 5.0 meters tall top to bottom, and 10.0 m long. The waves impacted every 6.0 s

Sonbull [250]

Answer:

more info

Explanation:

7 0

2 years ago

A glass ball of radius 3.74 cm sits at the bottom of a container of milk that has a density of 1.04 g/cm3. The normal force on t

Gelneren [198K]

Answer:

The mass of the ball is 0.23 kg

Explanation:

Given that

radius ,r= 3.74 cm

Density of the milk ,ρ = 1.04 g/cm³ = 1.04 x 10⁻³ kg/cm³

Normal force ,N= 9.03 x 10⁻² N

The volume of the ball V

$V=\dfrac{4}{3}\pi r^3$

$V=\dfrac{4}{3}\times \pi \times 3.74^3\ cm^3$

V= 219.13 cm³

The bouncy force on the ball = Fb

Fb = ρ V g

Fb + N = m g

m=Mass of the ball = Density x volume

m = γ V , γ =Density of the Ball

ρ V g + N = γ V g ( take g= 10 m/s²)

$\gamma =\dfrac{N+\rho V g}{V g}$

$\gamma =\dfrac{9.03\times 10^{-2}+1.04\times 10^{-3}\times 219.13\times 10}{219.13\times 10}$

γ = 0.00108 kg/cm³

m = γ V

m = 0.00108 x 219.13

m= 0.23 kg

The mass of the ball is 0.23 kg

5 0

3 years ago

Unless indicated otherwise, assume the speed of sound in air to be v = 344 m/s. A pipe closed at both ends can have standing wav

uranmaximum [27]

Answer:

68.8 Hz

137.6 Hz, 206.4 Hz

Explanation:

L = Length of tube = 2.5 m

v = Velocity of sound in air = 344 m/s

Distance between nodes is given by

$L=\dfrac{\lambda}{2}+m\dfrac{\lambda}{2}\\\Rightarrow \dfrac{\lambda(n+1)}{2}=L\\\Rightarrow \lambda=\dfrac{2L}{n+1}$

Where n = 0, 1, 2, 3, ...

Making n+1 = n

$\lambda=\dfrac{2L}{n}$

where n = 1, 2, 3 .....

For fundamental frequency n = 1

$\lambda=\dfrac{2\times 2.5}{1}\\\Rightarrow \lambda=5\ m$

Frequency is given by

$f=\dfrac{v}{\lambda}\\\Rightarrow f=\dfrac{344}{5}\\\Rightarrow f=68.8\ Hz$

The fundamental frequency is 68.8 Hz

First overtone

$2f=2\times 68.8=137.6\ Hz$

Second overtone

$3f=3\times 68.8=206.4\ Hz$

The overtones are 137.6 Hz, 206.4 Hz

4 0

3 years ago

How far did the object travel by the end of eight seconds, according to the graph above?

Ulleksa [173]

Answer:

<em>The object traveled 4 cm by the end of eight seconds.</em> Correct: A)

Explanation:

<u>Speed vs Time Graph</u>

In a speed-time graph, speed is plotted on the vertical axis and time is plotted on the horizontal axis. If the graph is a horizontal line, the speed is constant, if the line is sloped up, the speed is increasing and the acceleration is positive and constant, and if the line is sloped down, the speed is decreasing and the acceleration is negative and constant.

The distance traveled by the object can be found by calculating the area under the graph and above the x-axis.

The graph provided shows two different zones: the first 4 seconds, the speed is constant at 1 cm/s, and the last 4 seconds, the speed is zero, i.e. the object is not moving.

The area behind the first zone is a rectangle of height 1 cm/s and base 4 sec, thus the distance is 1 * 4 = 4 centimeters.

The second zone corresponds to an object at rest, thus no distance is traveled.

The object traveled 4 cm by the end of eight seconds.

A) Correct. As shown above

B) The distance traveled is 4 cm. Incorrect

C) The distance traveled is 4 cm. Incorrect

D) The distance traveled is 4 cm. Incorrect

6 0

3 years ago

What has more kinetic energy 15 kg ball rolling north at 15 m/s or a 15 kg ball rolling backwards at 7m/s

Setler79 [48]

Answer:

15 kg ball

Explanation:

6 0

3 years ago