3 years ago

Which of the following is an example of work being done on an object?

Physics

1 answer:

dlinn [17]3 years ago

6 0

Answer:

Explanation:

Work is defined as force x distance so a man pushing is the force and the couch moving is the distance

You might be interested in

John goes grocery shopping with his mother. His job is to push the cart. The cart is

lora16 [44]

Answer:

Beacause he has more grocceries and food heavy

Explanation:

7 0

3 years ago

Giving lots of points

bekas [8.4K]

Answer:

wind turbine

Explanation:

5 0

3 years ago

Read 2 more answers

7.22 Ignoring reflection at the air–water boundary, if the amplitude of a 1 GHz incident wave in air is 20 V/m at the water surf

Serga [27]

Answer:

z = 0.8 (approx)

Explanation:

given,

Amplitude of 1 GHz incident wave in air = 20 V/m

Water has,

μr = 1

at 1 GHz, r = 80 and σ = 1 S/m.

depth of water when amplitude is down to 1 μV/m

Intrinsic impedance of air = 120 π Ω

Intrinsic impedance of water = $\dfrac{120\pi}{\epsilon_r}$

Using equation to solve the problem

$E(z) = E_0 e^{-\alpha\ z}$

E(z) is the amplitude under water at z depth

E_o is the amplitude of wave on the surface of water

z is the depth under water

$\alpha = \dfrac{\sigma}{2}\sqrt{\dfrac{(120\pi)^2}{\Epsilon_r}}$

$\alpha = \dfrac{1}{2}\sqrt{\dfrac{(120\pi)^2}{80}}$

$\alpha =21.07\ Np/m$

now ,

$1 \times 10^{-6} = 20 e^{-21.07\times z}$

$e^{21.07\times z}= 20\times 10^{6}$

taking ln both side

21.07 x z = 16.81

z = 0.797

z = 0.8 (approx)

5 0

3 years ago

A cheetah can accelerate from rest at the rate of 4m /s

lesya [120]

Acceleration of cheetah (a) = 4m/s²
time = 10s
initial velocity(u) = 0
final velocity = v
distance travelled = s

v = u +at = 0 + 10×4 = 40m/s
s = (v²-u²)/2a = 40²/(2×4) = 1600/8 = 200m

6 0

3 years ago

Plss s ss s s s s s s s s

Crazy boy [7]

Answer:

i font know ewan madaling sabihin yan

8 0

2 years ago

Read 2 more answers