<span>3.2 grams
The first thing to do is calculate how many half lives have expired. So take the time of 72 seconds and divide by the length of a half life which is 38 seconds. So
72 / 38 = 1.894736842
So we're over 1 half life, but not quite 2 half lives. So you'll have something less than 12/2 = 6 grams, but more than 12/4 = 3 grams.
The exact answer is done by dividing 12 by 2 raised to the power of 1.8947. So let's calculate 2^1.8947 power
= 12 g / (e ^ ln(2)*1.8947)
= 12 g / (e ^ 0.693147181 * 1.8947)
= 12 g / (e ^ 1.313305964)
= 12 g / 3.718446464
= 3.227154167 g
So rounded to 2 significant figures gives 3.2 grams.</span>
Understanding the given:
85 kg mountain climber
6.50 m long rope
gravity = 10m/s2
If we want to identify the work done on this scenario
we get f = 85kg x 10m/s2 = 850 N
w = 850N x 6.5 m = 5525 J
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Answer:
at the melting point and boiling point
Explanation:
the heat abdorbed is used to break down the forces holding the particles together to allow it to change its state
The body systems that help cells get the energy they need are the digestive system and circulatory system. The first system is the digestive system because when you eat food, your body breaks it down using the stomach and other different parts of the digestive system. The next one is the circulatory system because your blood carries the nutrients you acquired from food you digested to the cells throughout your body.
Answer:
8000J
Explanation:
The kinetic energy of the car lost during breaking are converted to thermal energy and are gained by the brakes.
Kinetic energy loss by car = thermal energy gained by brakes.
∆K.E = ∆T.E ....1
The Kinetic energy loss by car can be expressed as;
∆K.E = K.E1 - K.E2
Initial K.E = K.E1 = 10000J
Final K.E = K.E2 = 2000J
∆K.E= 10000J - 2000J = 8000J
From equation 1,
∆K.E = ∆T.E
∆T.E = 8,000J
thermal energy gain by brakes = 8,000J
