Answer:
These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance. The example we will use here is ice melting into water.
Explanation:
Answer:
The size of the force that pushes the wall is 12,250 N.
Explanation:
Given;
mass of the wrecking ball, m = 1500 kg
speed of the wrecking ball, v = 3.5 m/s
distance the ball moved the wall, d = 75 cm = 0.75 m
Apply the principle of work-energy theorem;
Kinetic energy of the wrecking ball = work done by the ball on the wall
¹/₂mv² = F x d
where;
F is the size of the force that pushes the wall
¹/₂mv² = F x d
¹/₂ x 1500 x 3.5² = F x 0.75
9187.5 = 0.75F
F = 9187.5 / 0.75
F = 12,250 N
Therefore, the size of the force that pushes the wall is 12,250 N.
Answer: 20 newtons
Explanation:
Given that:
Force applied by Samantha = 10 newtons
Force applied by Emily = 10 newtons
Direction of both forces = same
Net force of their efforts = ?
Since net force of forces applied in the same direction is obtained by adding up the seperate forces applied, then
Net force = (10 newtons + 10 newtons)
Net force = 20 newtons
Thus, the net force of their efforts is 20 newtons.
Given that,
Radius of track, r = 50 m
time , t = 9 s
velocity, v = ?
Distance covered by car in one lap around a track is equal to the circumference of the track.
C = 2 π r = 2 * 3.14 * 50
C = 314.159 m
Distance covered by car, s = 314.159 m
Velocity = distance/ time
V = 314.159 / 9
V = 34.9 m/s
The average velocity of car is 34.9 m/s.
Answer:
v =25 m/s
time= 50 s
Velocity =Displacement/Time
Displacement = Velocity × Time
S = 25×50
s=1250m
Explanation:
v =25 m/s
time= 50 s
Velocity =Displacement/Time
Displacement = Velocity × Time
