Answer:
The mass is 
Explanation:
From the question we are told that
The initial temperature is 
The final temperature is 
Generally the maximum heat produced by 1 Liter of natural gas is 
So the amount of heat produced by 100 L is
=> 
Generally given that the efficiency is 
Then actual heat received by the water is
=> 
=> 
Converting to kcal
=> 
Generally the specific heat of water is
Generally the heat received by the water is mathematically represented as
=> 
=>
Answer:
Explanation:
In order to measure the coefficient of friction , we apply external force to move the body . When external force comes in motion , we adjust the external force so that it moves with zero acceleration or uniform velocity . In this case external force becomes equal to kinetic frictional force and then net force becomes zero because
net force = mass x acceleration = m x 0 = 0
Now frictional force = μ mg where μ is coefficient of kinetic friction
so F = μ mg where F is external force applied
μ = F / mg
Hence , to make external force equal to frictional force , it is necessary to make acceleration of body zero .
Answer:
The frictional force is 
Explanation:
From the question we are told that
The coefficient of kinetic force is μk = 0.35
The normal force felt by the puck is 
Generally the frictional force that acts on the puck is mathematically represented as
=> 
=>
The climate<span> was generally warmer and more humid than today, probably because of very active volcanism associated with unusually high rates of seafloor spreading.
</span><span>The first placental mammals appeared at the beginning of the Cretaceous. The Cretaceous saw the rise and extinction of the toothed birds, Hesperornis and Ichthyornis. The earliest fossils of birds resembling loons, grebes, cormorants, pelicans, flamingos, ibises, rails, and sandpipers were from the Cretaceous.</span>
A small 20-kg canoe is floating downriver at a speed of 2 m/s. 40 J is the canoe’s kinetic energy.
Answer: Option A
<u>Explanation:</u>
The given canoe has the mass and is being given to move at a speed. Therefore the kinetic energy of the canoe can be calculated using the following method,
Given that mass of the canoe = 20 kg and its speed =1 m/s
As we know that the Kinetic energy has the formula,
Therefore, substituting the value into the equation, we get,
= 40 J
