Answer:
K = 960 J
Explanation:
Given that,
Mass of a child = 20 kg
Mass of a sled = 10 kg
Speed of child on sled = 8 m/s
We need to find the kinetic energy of the sled with the child.
The total mass of child and the sled = 20 kg + 10 kg
= 30 kg
The formula for the kinetic energy of an object is given by :

Hence, the kinetic energy of the sled with the child is 960 J.
If it is in its ground state, it will be in the level 1s
Answer:
if we double the distance the energy stored will be doubled also
Explanation:
The energy stored in a capacitor is given as
Energy stored =1/2(cv²)
Or
= 1/2(Qv)
Where c = capacitance
Q= charge
But the electric field is expressed as
E= v/d
where v= voltage
d= distance
v=Ed
Substituting into any equation above say
Energy stored =1/2(Qv)
Substituting v=Ev
Energy stored =1/2(QEd)
From the equation above it shows that if we double the distance The energy stored will be doubled also
Answer: it is ultrasonic cleaners
Explanation: