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2 years ago

I need help

2 answers:

7 0

I like to just keep writing them over and over on a page also if you remember them just before the exam than as soon as you start write them on the front of your test so you don’t forget them.
Hope this helps.

Fantom [35]2 years ago

3 0

Try and make mnemonics out of them. So like h is happy (hydrogen) and so on?

You might be interested in

Jane has a mass of 55 kg and his body covers 700 nails with a surface area of 1.00 mm,

Oksana_A [137]

We have,

Jane mass is 55 kg
His body covered with 700 nails all of them having a surface area of 1.00 mm² each = 700 × 1 = 700 mm² = 700/1000000 = 7/10000

We know that,

Pressure = Force/Area

Let's calculate force as we already have area;

F = ma
F = 55 × 9.8 { Acceleration due to gravity }
F = 539 N

Now, if should she would be on 700 nails then pressure will be;

P = F/A
P = 539/7 × 10000
P = 5390000/7
P = 770,000 Pascal

And if should would be on a 1 nail only,

P = F/A
P = 539/1 × 1000000
P = 539000000 Pascal

As, you can notice yourself that the pressure will be so high with only 1 nail and because of this, nail will pass through jane's body.

6 0

2 years ago

A beam of protons is moving toward a target in a particle accelerator. This beam constitutes a current whose value is. (a) How m

Gelneren [198K]

Answer:

a. 5 × 10¹⁹ protons b. 2.05 × 10⁷ °C

Explanation:

Here is the complete question

A beam of protons is moving toward a target in a particle accelerator. This beam constitutes a current whose value is 0.42 A. (a) How many protons strike the target in 19 seconds? (b) Each proton has a kinetic energy of 6.0 x 10-12 J. Suppose the target is a 17-gram block of metal whose specific heat capacity is 860 J/(kg Co), and all the kinetic energy of the protons goes into heating it up. What is the change in temperature of the block at the end of 19 s?

Solution

i = Q/t = ne/t

n = it/e where i = current = 0.42 A, n = number of protons, e = proton charge = 1.602 × 10⁻¹⁹ C and t = time = 19 s

So n = 0.42 A × 19 s/1.602 × 10⁻¹⁹ C

= 4.98 × 10¹⁹ protons

≅ 5 × 10¹⁹ protons

The total kinetic energy of the protons = heat change of target

total kinetic energy of the protons = n × kinetic energy per proton

= 5 × 10¹⁹ protons × 6.0 × 10⁻¹² J per proton

= 30 × 10⁷ J

heat change of target = Q = mcΔT ⇒ ΔT = Q/mc where m = mass of block = 17 g = 0.017 kg and c = specific heat capacity = 860 J/(kg °C)

ΔT = Q/mc = 30 × 10⁷ J/0.017 kg × 860 J/(kg °C)

= 30 × 10⁷/14.62

= 2.05 × 10⁷ °C

5 0

2 years ago

A cyclist and his bicycle have a combined mass of 88 kg and a combined

SpyIntel [72]

Answer:D

Explanation:

Mark brainly

5 0

2 years ago

A student uses two magnets to pick iron screws out of a pile of scraps. Would more magnets attached to the top of the first two

Bond [772]

Answer:

any type of magnet or the number of magnet dosent matter its what matters is that iron is attracted to a magnet . Because iron is a metal and metals always attract magnet or any magenetic objects .

Explanation:

5 0

2 years ago

An internal combustion engine uses fuel, of energy content 44.4 MJ/kg, at a rate of 5 kg/h. If the efficiency is 28%, determine

Alika [10]

Efficiency = Power Output / Power Input

Power Input = Rate of Energy input = 44.4 MJ/kg * 5 kg/h

= 222 MJ/h

But 1 hour = 3600seconds

222 MJ/h = 222 MJ/3600s = 0.061667 MW J/s = Watts

Power input = 0.061667 MW = 61 667 W

From Efficiency = Power Output / Power Input

   28% = Power Output / 61667

   Power Output = 0.28 * 61667

   Power Output = 17266.76 W

    Power Output ≈ 17 267 W

   Rate of heat rejection = Power Input - Power Output

   = 61667 - 17267 = 44400 W

   Rate of heat rejection = 44 400W.

8 0

3 years ago