The molecules which evaporate presumably take heat away from the liquid. So, I'd disagree with the classmate. Whether the amount of cooling would differ from the usual case wherein the molecules have different speeds is another question.
I guess the argument goes something along the lines of that the faster moving and therefore most kinetically energetic molecues evaporate and take away most heat. But if there's no faster moving molecules, 'cos they all have the same speed well, then presumably they'd all take away the same amount of heat. So, maybe the cooling would be less. No cooling though ??? Hmmmm dunno .... i think not ....
Answer:
Average speed: 86 km/h
Explanation:
Driving from San Antonio to Houston:
1st. half time: 54km/h
2nd. half time: 118 km/h
Average speed = [tex] \frac{54 \frac{km}{h}+ 118 \frac{km}{h} }{2}=86 \frac{km}{h} [\tex]
Driving way back:
1st. half time: 54km/h
2nd. half time: 118 km/h
Average speed = [tex] \frac{54 \frac{km}{h}+ 118 \frac{km}{h} }{2}=86 \frac{km}{h} [\tex]
As in both routes we have the same average speed, then the average speed for the whole trip is 86 km/h
Answer:
The volume of water displaced the same as the volume of the block.
Explanation:
With respect to the principle of floatation, when an object floats in a fluid; its weight is the same as the volume of the fluid displaced.
The volume of the block relates to is dimension and size which can be compared with the volume of the fluid displaced. When the block is floats in water, it would displace a reasonable volume of water. Thus, it would be expected that the volume of water displaced by the block is equal to the volume of the block.
Answer:
The needed force is 35,000 N.
Explanation:
By the second Newton's law, we know that:
F = M*a
Force equals mass times acceleration.
If we know that the mass of the car is 1750kg, then M = 1750kg, and the acceleration is 20 m/s^2, then a = 20m/s^2
We can replace these values in the original equation to find the value of F.
F = 1750kg*20 m/s^2 = 35,000 N