Where is 3cm on a ruler

You leave your home at 1pm. At 3pm, you are 100 km east of your house. What was your average velocity in km/hr

Rasek [7]

Answer:

50km/h

Explanation:

Average velocity = change in distance (or distance travelled) divided by/ the change in time (or time taken.)

The change in distance has been given as 100km.

The change in time is 3pm-1pm = 2 hours.

Therefore the average velocity was 100/2 = 50km/h (to the east).

Hope this helped!

4 0

3 years ago

How much electrical energy is used by a 75 W laptop that is operating for 12 minutes?

Liono4ka [1.6K]

"1 watt" means 1 joule of energy per second.

75 W means 75 joules/sec .

Energy = (75 Joule/sec) x (12 min) x (60 sec/min)

Energy = (75 x 12 x 60) (Joule-min-sec / sec-min)

Energy = 54,000 Joules

7 0

3 years ago

A 3.50-m-long, 380kg steel uniform beam extends horizontally from the point where it has been bolted to the framework of a new b

LenKa [72]

Answer:

9064.44 Nm

Explanation:

Since the steel is uniform, the center of mass is also at the geometric center, which is 3.5 / 2 = 1.75 m from the bolted point.

Let g = 9.81 m/s2. The weight of the beam and the worker is

$W_b = m_bg = 380*9.81 = 3727.8 N$

$W_w = m_wg = 74*9.81 = 725.94N$

So the total torque about the bolted point is the sum of product of weights and distances from weight to the bolted point

$W_b*1.75 + W_w*2.4 = 3727.8 *1.75 + 725.94 * 3.5 = 9064.44 Nm$

8 0

3 years ago

One circuit contains only an ac generator and a resistor, and the rms current in this circuit is IR. Another circuit contains on

snow_tiger [21]

Answer:

1/3 times.

Explanation:

Let V₀ be the peak voltage .

IR ( rms ) = ( V₀ / √2 R )

R is value of resistance

IC = ( V₀ ωC / √2 )

( 1 / ωC is reactance of capacitance in ac circuit )

$\frac{I_R}{I_C} =\frac{\frac{V_0}{\sqrt{2}R } }{\frac{V_0\omega C}{\sqrt{2} } }$

= $\frac{I_R}{I_C} = \frac{1}{\omega C R}$

When frequency is tripled angular frequency will also be tripled

hence the ratio $\frac{I_R}{I_C}$ becomes 1/3 times.

7 0

3 years ago

Represent 7468 N with SI units having an appropriate prefix. Express your answer to four significant figures and include the app

sergeinik [125]

Answer:

7.468 kN

Explanation:

Here the force of 7468 Newton is given.

Some of the prefixes of the SI units are

kilo = 10³

Mega = 10⁶

Giga = 10⁹

The number is 7468.0

Here, the only solution where the number of significant figures is kilo

1 kilonewton = 1000 Newton

$1\ Newton=\frac{1}{1000}\ kilonewton$

$\\\Rightarrow 7468\ Newton=\frac{7468}{1000}\ kilonewton\\ =7.468\ kilonewton$

So 7468 N = 7.468 kN

3 0

3 years ago