Ask question

Ask question

All categories

1 year ago

14

Danielle is doing some DIY. She uses a 1.2kW electric saw for 20 minutes and then a 1000W electric sander for half an hour. Whic

h job is the more expensive in terms of electricity used - sawing or sanding?

1 answer:

mixas84 [53]1 year ago

4 0

Answer:

1.2kw because it is kilowatt

You might be interested in

Kathmandu lies at high altitude than biratnagar from sea level.Where does an object has more weight between two places?Give reas

Alla [95]

Answer:

Kathmandu

Explanation:

As the altitude get higher, the gravitational pull of the earth on the object increases, therefore, the mass is higher up above.

8 0

2 years ago

What is the formula that can be used to find velocity if kinetic energy and mass are known?

viva [34]

The formula for kinetic energy is $\frac{1}{2}m\Delta v^2$ . Thus, the equation for velocity is $v= \sqrt{ \frac{2TotalKineticEnergy}{m} }$ .

6 0

2 years ago

Read 2 more answers

If a young protostar with a disk is rotating and shrinking. how much faster is it rotating after its size has decreased by a fac

maks197457 [2]

In this system we have the conservation of angular momentum: L₁ = L₂
We can write L = m·r²·ω

Therefore, we will have:
m₁ · r₁² · ω₁ = m₂ · r₂² · ω₂

The mass stays constant, therefore it cancels out, and we can solve for ω<span>₂:
</span>ω₂ = (r₁/ r₂)² · ω<span>₁

Since we know that r</span>₁ = 4r<span>₂, we get:
</span>ω₂ = (4)² · ω<span>₁
= 16 </span>· ω<span>₁

Hence, the protostar will be rotating 16 </span><span>times faster.</span>

5 0

2 years ago

Little Tammy lines up to tackle Jackson to (unsuccessfully) prove the law of conservation of momentum. Tammy’s mass is 34.0 kg a

Naily [24]

Answer:

So Tammy must move with speed 4.76 m/s in opposite direction of Jackson

Explanation:

As per law of conservation of momentum we know that there is no external force on it

So here we can say that initial momentum of the system must be equal to the final momentum of the system

now we have

$m_1v_1 + m_2v_2 = 0$

final they both comes to rest so here we can say that final momentum must be zero

now we have

$34 v + 54 (3 m/s) = 0$

$v = -4.76 m/s$

8 0

1 year ago

Two objects move toward each other because of gravitational attraction. As the objects get closer and closer, the force between

bearhunter [10]

<span>Two objects move toward each other because of gravitational attraction. As the objects get closer and closer, the force between them increases. </span>

5 0

1 year ago

Read 2 more answers