Answer:
Mass is how much space the object takes up and how much it has inside, and weight is how heavy the object is.
Explanation: Hope this helps ;)
Answer:
96%
Explanation:
To find the values of the motor efficiency you use the following formula:

P_o: output power = 864J/0.5min=864J/30s=28.8W
P_i: input power = I*V = (3A)(12V) = 36W
By replacing this values you obtain:

hence, the motor efficiency is about 96%
traslation:
Pentru a găsi valorile eficienței motorului, utilizați următoarea formulă:
P_o: putere de ieșire = 864J / 0.5min = 864J / 30s = 28.8W
P_i: putere de intrare = I * V = (3A) (12V) = 36W
Înlocuind aceste valori obțineți:
prin urmare, eficiența motorului este de aproximativ 96%
Answer:
a) 37.8 W
b) 2 Nm
Explanation:
180 g = 0.18 kg
We can also convert 180 revolution per minute to standard angular velocity unit knowing that each revolution is 2π and 1 minute equals to 60 seconds
180 rpm = 180*2π/60 = 18.85 rad/s
We can use the heat specific equation to find the rate of heat exchange of the steel drill and block:

Since the entire mechanical work is used up in producing heat, we can conclude that the rate of work is also 37.8 J/s, or 37.8 W
The torque T required to drill can be calculated using the work equation



<h2>Answer with Explanation </h2>
Dalton’s theory can be classified by the following hypotheses:
1) All material was formed of particles, unbreakable and strong construction segments.
2) All particles of a given component are indistinguishable in volume and characteristics
3) Compounds are determined by a mixture of two or more distinct kinds of atoms.
4) Chemical responses appeared in the rearrangement of the reacting atoms.
This theory was to explain all matter in terms of atoms and their characteristics, the law of conservation of volume and the law of constant composition.