Ask question

Ask question

All categories

2 years ago

9

Many people choose to buy expensive low energy lamps instead of cheaper filament lamps.Give two reasons for this

1 answer:

valkas [14]2 years ago

6 0

This is because they use less energy and also they seem to last longer.

You might be interested in

Mechanical waves can travel through _______.

eimsori [14]

mediums only, mechanical waves always propagate through medium

5 0

2 years ago

What is net force?

drek231 [11]

The answer is d my friend :)

5 0

2 years ago

Read 2 more answers

A marble, a bowling ball, a basketball, and a baseball are rolling across the floor at 1.0 m/s. Which one has the greatest kinet

sveticcg [70]

Answer: A Bowling Ball

Explanation:

A body possess kinetic energy due to virtue of its motion. It depends on the mass of the body and the speed with which it is travelling.

K.E = 0.5 mv²

K.E. ∝ m

It is given that the marble, bowling ball, basketball and baseball all are rolling with the same speed. This means that the greatest energy would be possessed by the body having greatest mass.

On an average the mass of a marble is about 50 g, mass of a bowling ball is 750 g, mass of baseball is 150 g and mass of basketball is 600 g. Since the mass of a Bowling ball is the greatest, it would possess the greatest kinetic energy.

3 0

3 years ago

Read 2 more answers

A sphere of plastic of radius = .100 m is completely immersed in water. The density of the plastic is 600 kg/m3. Since the plast

tekilochka [14]

To solve this problem we need to use the proportional relationships between density, mass and volume, together with Newton's second law.

The force can be described as

$F = ma \rightarrow mg$

Where,

m = Mass

g = Gravitational acceleration

At the same time the Density can be defined as

$\rho = \frac{m}{V} \rightarrow m = \rho V$

Where,

m = mass

V = Volume

Replacing the value of the mass at the equation of Force we have,

$F = \rho V g$

Since the difference between the two forces gives us the total Force then we have to

$F_T = F_w - F_p$

Where

$F_w =$ Force of the water

$F_p$ = Force of plastic

Therefore with the values for this force we have,

$F_T = \rho_w Vg - \rho_p Vg$

$F_T = Vg(\rho_w - \rho_p)$

$F_T = (\frac{4}{3} \pi r^3) g(\rho_w - \rho_p)$

$F_T = (\frac{4}{3} \pi (0.1)^3) (9.8)(1000 - 600)$

$F_T = 16.412 N$

Therefore the tension in the thread is 16.412N

3 0

3 years ago

A ball is kicked horizontally at 4.6 m/s off of a cliff 13.4 m high. How far from the cliff will it land.

Mekhanik [1.2K]

<h3>Answer:</h3>

7.53 m

<h3>Explanation:</h3>

<u>We are given:</u>

Initial Horizontal Velocity of the Ball = 4.6 m/s

Initial Vertical Velocity of the Ball = 0 m/s

Height from which ball is kicked = 13.4 m

<u>Time taken by the ball to reach the ground:</u>

The ball has an initial vertical velocity of 0 m/s

it also has a downward acceleration of 10 m/s² due to gravity

<u>Solving for the time taken:</u>

s = ut + 1/2(at²) [second equation of motion]

replacing the values

13.4 = (0)(t) + 1/2 (10)(t²)

13.4 = 5t²

t² = 13.4/5 [dividing both sides by 5]

t² = 2.68

t = 1.637 seconds [taking the square root of both sides]

<u>Horizontal distance covered by the ball:</u>

Since there are no horizontal opposing forces on the ball,

the ball will more horizontally at a velocity of 4.6 m/s until it hits the ground

We calculated that the ball will hit the ground in 1.637 seconds

<u>Distance covered:</u>

s = ut + 1/2 (at²) [seconds equation of motion]

s = ut [since a = 0m/s² in the horizontal plane]

replacing the values

s = 4.6 * 1.637

s = 7.53 m

Hence, the ball landed 7.53 m from the cliff

5 0

2 years ago