Answer:84.672 joules.
Explanation:
1) Data:
m = 7.2 kg
h = 1.2 m
g = 9.8 m / s²
2) Physical principle
Using the law of mechanical energy conservation principle, you have that the kinetic energy of the dog, when it jumps, must be equal to the final gravitational potential energy.
3) Calculations:
The gravitational potential energy, PE, is equal to m × g × h
So, PE = m × g × h = 7.2 kg × 9.8 m/s² × 1.2 m = 84.672 joules.
And that is the kinetic energy that the dog needs.
Answer:
A) False
B) False
C) True
D) False
Explanation:
A) False, because when leaving the field, the coil experiences a magnetic force to the right.
B) When the loop is entering the field, the magnetic flux through it will increase. Thus, induced magnetic field will try to decrease the magnetic flux i.e. the induced magnetic field will be opposite to the applied magnetic field. The applied magnetic field is into the plane of figure and thus the induced magnetic field is out of the plane of figure. Due to that reason, the current would be counterclockwise. So the statement is false.
C) When the loop is leaving the field, the magnetic flux through the loop will decrease. Thus, induced magnetic field will try to increase the magnetic flux i.e. the inducued magnetic field will be in the same direction as the applied magnetic field. The applied magnetic field is into the plane of figure and thus the induced magnetic field is also into the plane of figure. Due to that reason, the current would be clockwise. So the statement is true.
D) False because when entering the field magnetic force will be toward left side
Answer:
block 2 or 4
because of the distribution of weight and force being applied to the object
Answer:
Stretch can be obtained using the Elastic potential energy formula.
The expression to find the stretch (x) is 
Explanation:
Given:
Elastic potential energy (EPE) of the spring mass system and the spring constant (k) are given.
To find: Elongation in the spring (x).
We can find the elongation or stretch of the spring using the formula for Elastic Potential Energy (EPE).
The formula to find EPE is given as:
Rewriting the above expression in terms of 'x', we get:
Example:
If EPE = 100 J and spring constant, k = 2 N/m.
Elongation or stretch is given as:
Therefore, the stretch in the spring is 10 m.
So, stretch in the spring can be calculated using the formula for Elastic Potential Energy.
