Answer:
Car A has twice the energy of car B.
Explanation:
The kinetic energy of an object is given by :
Where
m is the mass
v is the speed of the object
Car A has twice the mass of Car B. Both travel at the same speed i.e.
So,
So, the kinetic energy of car A is twice of the kinetic energy of car B.
B. Learn and follow the local rules about open fires, camp stoves, kerosene lanterns, and other sources of fire.
Answer:
1. False
2. True
3. True
Explanation:
1- False —> The relation between electric potential and electric field is given such that
Therefore, for a uniform E field, electric potential is linearly proportional to the distance.
2- True —> The electric field lines always cross the equipotential lines perpendicularly.
3- True —> In order to be a potential difference, one source of electric field is enough. The electric potential will decrease radially according to the following formula:
There is no test charge in the formula, only the source charge. Even when there is no test charge, the potential difference between points in space can exist.
Answer:
A skater glides along a circular path. She defines a certain point on the circle as her origin. Later on, she passes through a point at which the distance she has traveled along the path from the origin is smaller than the magnitude of her displacement vector from the origin.
So here in circular motion of the skater we can see that the total path length of the skater is along the arc of the circle while we can say that displacement is defined as the shortest distance between initial and final position of the object.
So it is not possible in any circle that arc-length is less than the chord joining the two points on the circle
As we know that arc length is given as
length of chord is given as
so here
so we have
Answer:
the height above the ground through Mr. Voytko lifted the apple is 2.5 m.
Explanation:
Given;
energy of Mr. Voytko, E = 7.35 J
mass of the apple, m = 0.3 kg
Apply the principle of conservation of energy.
Energy of Mr. Voytko = Potential energy of the apple due to its height above the ground.
E = mgh
where;
h is the height above the ground through Mr. Voytko lifted the apple.
g is acceleration due to gravity = 9.8 m/s²
h = E / (mg)
h = 7.35 / (0.3 x 9.8)
h = 2.5 m
Therefore, the height above the ground through Mr. Voytko lifted the apple is 2.5 m.