Answer:
Activation Energy
Explanation:
Effective collisions are those that result in a chemical reaction. In order to produce an effective collision, reactant particles must possess some minimum amount of energy. This energy, used to initiate the reaction, is called the activation energy.
Answer:
Option e) 320 s
Explanation:
Here, distance = 3.0 km = 3000 m
The velocity of boat when it is going upstream;
Upstream velocity = velocity of boat in still water - velocity of river flow
So, Upstream velocity 
So,Time to go upstream

The velocity of boat when it is going downstream;
Downstream velocity = velocity of boat in still water + velocity of river flow
So, Downstream velocity 
So,Time to go downstream

So, total time (t) = 
Option E is the correct answer.
The heat needed is given by Mcθ , where m is the mass in Kg, c is the heat capacity of aluminium, and θ is the change in temperature.
Specific heat capacity of aluminium is 0.9 j/g°c
thus; Heat = 55 × 0.9 × 72.2
= 3573.9 Joules or 3.574 kJ
The mass (in kg) of water in the pool is 1.264
kg.
<h3>What is mass?</h3>
A numerical measurement of inertia, a basic characteristic of all matter, in physics. It essentially refers to a body of matter's resistance to changing its speed or location in response to the application of a force. The change caused by an applied force is smaller the more mass a body has.
Mass is a physical body's total amount of matter. Inertia, or the body's resistance to acceleration when a net force is applied, is also measured by this term. The strength of an object's gravitational pull to other bodies is also influenced by its mass. The kilogram serves as the SI's fundamental mass unit.
Given: A pool is 31.4 m long and 40.0 m wide. if the average depth of water is 3.30 ft
31.4
40.0 = 1256 
1 m = 39.37 in = 3.28 ft
3.30 ft = 1.01 m
Volume of pool = 1256
1.01 = 1264 
Since 1
water contains
the volume of the pool is
1.264 E3
E3 = 1.264E6 kg
(or 1.264
kg)
The mass (in kg) of water in the pool is 1.264
kg.
To learn more about mass refer to:
brainly.com/question/19385703
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