Shale, sandstone, and limestone are the most commoc types of sedimentary rocks. They are formed by the most common mineral that is found on or near the surface of the Earth

4 0

3 years ago

a dump truck travels 70mph for 3 hours, then for 20mph for another 2 hours in the same direction. what is the average speed the

Dmitry_Shevchenko [17]

Answer:

the average speed of the car is 170 mph.

Explanation:

Given;

initial speed, u = 70 mph

time of motion, t₁ = 3 hours

final speed, v = 20 mph

time of motion, t₂ = 2 hours

The average speed of the car is calculated as;

$v' = \frac{70(3) - 20(2)}{3-2} \\\\v' = 170 \ mph$

Therefore, the average speed of the car is 170 mph.

8 0

2 years ago

2. An alternating current is represented by the equation I=20sin 100mt.

Sladkaya [172]

Explanation:

The general equation of an AC current is given by :

$I=I_o sin\omega t$

Where

I₀ is the peak value of current

$\omega$ is angular frequency

$As\ \omega=2\pi f$

So,

$f=\dfrac{\omega}{2\pi}\\\\f=\dfrac{100\pi}{2\pi}\\\\f=50\ Hz$

We know that,

$I_{rms}=\dfrac{I_0}{\sqrt{2}}\\\\=\dfrac{20}{\sqrt{2}}\\\\I_{rms}=14.14\ A$

So, the frequency is 50 Hz and the maximum rms value of current is 14.14 A.

3 0

2 years ago

Which statement correctly explains mechanical advantage?

Shtirlitz [24]

I'm not entirely sure but I would think it's A.

4 0

2 years ago