All categories

3 years ago

How long was a 60 W light bulb turned on if it used a total of 580 J of energy?

1 answer:

7 0

Here's the tool you need. You can't answer the question without this:

   "1 watt"
means
   "1 joule of energy, generated, used, or moved, every second".

So 60 watts = 60 joules per second

   Total energy generated,
      used, or moved = (power) x (time).

   580 joules = (60 watts) x (time)

Divide each side
by (60 watts): Time = (580 joules) / (60 joules/sec)

   = (9 and 2/3) seconds .

You might be interested in

A toy helicopter takes off and moves 6 m up and then 1 m back down. What

klio [65]

the answer is 5 m up AKA "B"

6 0

3 years ago

A small, single engine airplane is about to take off. The airplane becomes airborne, when its speed reaches 193.0 km/h. The cond

siniylev [52]

Answer:

513 m

Explanation:

We have;

final speed of the airplane = 193.0 km/h * 1000/3600 = 53.6 m/s

acceleration of the air plane = 2.80 m/s2

initial velocity of the airplane = 0 m/s

length of the runway = distance covered

v^2 = u^2 + 2as

v^2 - u^2 = 2as

s = v^2 - u^2/2a

s = (53.6)^2 - 0^2/ 2 * 2.80

s = 2872.96/ 5.6

s = 513 m

4 0

3 years ago

A 900 N crate is being pulled across a level floor by a force F of 340 N at an angle of 23° above the horizontal. The coefficien

Olegator [25]

Answer:

0.958891203 m/s²

Explanation:

N = Weight of crate = 900 N

$\mu$ = Coefficient of friction = 0.25

Force of friction acting on the force applied

$f=\mu N\\\Rightarrow f=0.25\times 900\\\Rightarrow f=225\ N$

Force used to pull the crate

$F=340cos 23\\\Rightarrow F=312.97165\ N$

The net force is

$F_n=F-f\\\Rightarrow F_n=312.97167-225\\\Rightarrow F_n=87.97167\ N$

Acceleration is given by

$a=\frac{F_n}{m}\\\Rightarrow a=\dfrac{87.97167}{\dfrac{900}{9.81}}\\\Rightarrow a=0.958891203\ m/s^2$

The magnitude of the acceleration of the crate is 0.958891203 m/s²

4 0

3 years ago

Power is __________________. Power is __________________. the work done by a system the force required to push something the spe

DaniilM [7]

Answer:

The rate at which the energy of a system is transformed

Explanation:

Power is the rate at which energy of a system is transformed or the rate at which work is done. It is defined by Power = Workdone/time taken

Its unit is the Watt denoted by the letter W.

For example, assuming a work of 200 J is done in 10 s, then Power, P equals

P = workdone/time taken = 200 J/10 s = 20 J/s = 20 W

6 0

3 years ago

A metal ball of mass 100 g is heated to 90°C and then cooled to 25°C. The heat lost in the process is 2.5 kJ. Another metal ball

kobusy [5.1K]

Explanation:

q = mCΔT

where q is heat,

m is mass,

C is specific heat capacity,

and ΔT is temperature change.

For the first ball:

2500 J = (100 g) C (90°C − 25°C)

C = 0.385 J/g/°C

For the second ball:

5000 J = (200 g) C (90°C − 25°C)

C = 0.385 J/g/°C

The two metals have the same specific heat, and are likely the same metal (possibly copper or zinc).

3 0

3 years ago

Read 2 more answers