<span>A fence runs all the way around the house but never moves.</span>
Answer:
1.92 J
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 200 Kg
Spring constant (K) = 10⁶ N/m
Workdone =?
Next, we shall determine the force exerted on the spring. This can be obtained as follow:
Mass (m) = 200 Kg
Acceleration due to gravity (g) = 9.8 m/s²
Force (F) =?
F = m × g
F = 200 × 9.8
F = 1960 N
Next we shall determine the extent to which the spring stretches. This can be obtained as follow:
Spring constant (K) = 10⁶ N/m
Force (F) = 1960 N
Extention (e) =?
F = Ke
1960 = 10⁶ × e
Divide both side by 10⁶
e = 1960 / 10⁶
e = 0.00196 m
Finally, we shall determine energy (Workdone) on the spring as follow:
Spring constant (K) = 10⁶ N/m
Extention (e) = 0.00196 m
Energy (E) =?
E = ½Ke²
E = ½ × 10⁶ × (0.00196)²
E = 1.92 J
Therefore, the Workdone on the spring is 1.92 J
Answer:
4m/s^2
Explanation:
mass(m)=20 kg
force=80 N
acceleration (a)=?
Therefore,
Force = mass * acceleration
80 = 20*a
a=80/20
=4m/s^2
Answer : The correct option is, (c) 
Explanation :
First we have to calculate the energy or heat.
Formula used :

where,
E = energy (in joules)
V = voltage (in volt)
I = current (in ampere)
t = time (in seconds)
Now put all the given values in the above formula, we get:


Now we have to calculate the heat capacity of the calorimeter.
Formula used :

where,
C = heat capacity of the calorimeter
= initial temperature = 
= final temperature = 
Now put all the given values in this formula, we get:


Therefore, the heat capacity of the calorimeter is, 
الجواب هو الأول الجواب هو الأول