All categories

4 years ago

When you do positive work on an object, you ______

Physics

2 answers:

guajiro [1.7K]4 years ago

4 0

C. increase the object's energy

gtnhenbr [62]4 years ago

3 0

when you do positive work on an object, you ______

A. decrease the object's energy

B. keep the object's energy the same 

C. increase the object's energy

D. may increase or decrease the object's energy

You might be interested in

What is the wavelength of an earthquake wave if it has a speed of 3 km/s and a frequency of 6 Hz?

disa [49]

Wavelength = c/f.
Wavelength =0.5km

8 0

3 years ago

39 g aluminum spoon (specific heat 0.904 J/g·°C) at 24°C is placed in 166 mL (166 g) of coffee at 83°C and the temperature of th

tatuchka [14]

Answer: The final temperature of the solution is $80.14^oC$

Explanation:

The amount of heat released by coffee will be absorbed by aluminium spoon.

Thus, $\text{heat}_{absorbed}=\text{heat}_{released}$

To calculate the amount of heat released or absorbed, we use the equation:

$Q=m\times c\times \Delta T=m\times c\times (T_{final}-T_{initial})$

Also,

$m_1\times c_1\times (T_{final}-T_1)=-[m_2\times c_2\times (T_{final}-T_2)]$ ..........(1)

where,

q = heat absorbed or released

$m_1$ = mass of aluminium = 39 g

$m_2$ = mass of coffee = 166 g

$T_{final}$ = final temperature = ?

$T_1$ = temperature of aluminium = $24^oC$

$T_2$ = temperature of coffee = $83^oC$

$c_1$ = specific heat of aluminium = $0.904J/g^oC$

$c_2$ = specific heat of coffee= $4.1801J/g^oC$

Putting all the values in equation 1, we get:

$39\times 0.904\times (T_{final}-24)=-[166\times 4.1801\times (T_{final}-83)]$

$T_{final}=80.14^oC$

Hence, the final temperature of the solution is $80.14^oC$

4 0

4 years ago

i cant figure out how to delete a question on this website. so i am writing this until i figure it out.

sergij07 [2.7K]

Answer:

I'm guessing it would remain a mystery to us all

5 0

3 years ago

How many watts are used when 6000 joules of energy are consumed in 5 hours?

Ray Of Light [21]

Power = energy / time
Time should be in seconds
5 hours = 5 × 60 minutes = 5 × 60 ×60 seconds = 18000 s
Power = 6000/18000 = 0.333 W

Hope it helped!

7 0

3 years ago

A 1.2 g pebble is stuck in a tread of a 0.76 m diameter automobile tire, held in place by static friction that can be at most 3.

Maksim231197 [3]

Answer:

$v=33.764m/s$

Explanation:

Given data

Mass m=1.2 g=0.0012 kg

diameter d=0.76 m

Friction Force F=3.6 N

To find

Velocity v

Solution

From the Centripetal force we know that

$F_{c}=\frac{mv^{2} }{r}$

Where m is mass

v is velocity

r is radius

Substitute the given values to find velocity v

$F_{c}=\frac{mv^{2} }{r}\\v^{2}=\frac{F_{c}(r)}{m}\\ v=\sqrt{\frac{F_{c}(r)}{m}}\\ v=\sqrt{\frac{F_{c}(diameter/2)}{m}}\\v=\sqrt{\frac{(3.6N)(0.76/2)m}{(0.0012kg)}}\\v=33.764m/s$

4 0

3 years ago