The wasted energy in a charger is:

Which two chemists organized elements based on properties such as how the elements react or whether they are solid or liquid

Lelechka [254]

Doberiner and lavoiser

5 0

3 years ago

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Two balls are thrown from a cliff. One is thrown directly up, the other directly down. Both balls have the same initial speed, a

Otrada [13]

Answer:

both the same

Explanation:

When a ball is thrown vertically upwards, it experiences that same acceleration due to gravity as an object thrown directly downwards.

This means that if we ignore the effects of air resistance, and the two balls have the same initial speed, they are expected both expected to hit the ground at the same speed as a result of the principle of conservation of energy.

8 0

3 years ago

A disk of radius 25 cm spinning at a rate of 30 rpm slows to a stop over 3 seconds. What is the angular acceleration? B. How man

Ne4ueva [31]

Answer:

A. α = - 1.047 rad/s²

B. θ = 14.1 rad

C. θ = 2.24 rev

Explanation:

A.

We can use the first equation of motion to find the acceleration:

$\omega_f = \omega_i + \alpha t$

where,

ωf = final angular speed = 0 rad/s

ωi = initial angular speed = (30 rpm)(2π rad/1 rev)(1 min/60 s) = 3.14 rad/s

t = time = 3 s

α = angular acceleration = ?

Therefore,

$0\ rad/s = 3.14\ rad/s + \alpha(3\ s)$

α = - 1.047 rad/s²

B.

We can use the second equation of motion to find the angular distance:

$\theta = \omega_it +\frac{1}{2}\alpha t^2\\\theta = (3.14\ rad/s)(3\ s) + \frac{1}{2}(1.04\ rad/s^2)(3)^2$

θ = 14.1 rad

C.

θ = (14.1 rad)(1 rev/2π rad)

θ = 2.24 rev

6 0

3 years ago

Which property of water causes the cracks in the pavement in cold climates ?

amid [387]

“As temperatures drop, the pavement contracts, building up tensile stresses that lead to cracking,” states MnDOT's Research Services Section. “Fractures occur every 20 to 30 feet across the lane, allowing water to penetrate the structure, which further weakens the pavement layer and the base beneath

7 0

3 years ago

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Question#7:a) A television uses 1500J of electric energy to produce 1100J 1 point

Vesnalui [34]

Answer:

a.73.3%

b.26.6%

Explanation:

a. The efficiency is the energy output, divided by the energy input, and expressed as a percentage.

#Given the energy input as 1500J and the subsequent output as 1100J, the TV's efficiency is calculated as:

$\eta=\frac{E_o}{E_i}\\\\=\frac{1100}{1500}\times 100\%\\\\=73.33\%$

Hence, the TV has an efficiency of 33.3%

b. From a above, we know that the TV has an output of 1100J and input of 1500J.

-We therefore calculate it's wastage as the difference between output and input:

Wastage=Energy Input-Energy Output=1500J-1400J=400J

$E_w=\frac{E_{wasted}}{E_i}\times 100\%\\\\=(400/1500)\times100\%\\\\=26.67\%$

Hence, the TV has wasted of 26.6%

4 0

3 years ago