Answer:
His kinetic energy increases, potential energy decreases
The sum of kinetic and potential energy is a constant at any instant before he comes to rest.
Explanation:
Snowboarder is starting from a height and moving to the down direction. As he moves down his velocity increases, we know that kinetic energy is given by the expression 
, so as he moves his kinetic energy increases.
When the snowboarder is starting his potential energy is maximum(Potential energy = mgh), as he comes down his potential energy decreases.
Based on this we can conclude that the sum of potential energy and kinetic energy is a constant at any instant for a snowboarder before he comes to rest.
mgh+= Constant
Answer:
C) If an ice cube is placed into a boiling water, then it will melt in less than 2 minutes.
Explanation:
Responder:
E = 1440 kJ
Explicación:
Se da que,
La potencia de un horno de cocción es de 800 W
El voltaje al que se opera es de 230 V
Tiempo, t = 30 minutos = 1800 segundos
Necesitamos encontrar la energía eléctrica utilizada por el horno de cocción. El producto de la potencia y el tiempo es igual a la energía consumida. Entonces,
Answer:
Coefficient of kinetic friction = 0.146
Explanation:
Given:
Mass of sled (m) = 18 kg
Horizontal force (F) = 30 N
FInal speed (v) = 2 m/s
Distance (s) = 8.5 m
Find:
Coefficient of kinetic friction.
Computation:
Initial speed (u) = 0 m/s
v² - u² = 2as
2(8.5)a = 2² - 0²
a = 0.2352 m/s²
Nweton's law of :
F (net) = ma
30N - μf = 18 (0.2352)
30 - 4.2336 = μ(mg)
25.7664 = μ(18)(9.8)
μ = 0.146
Coefficient of kinetic friction = 0.146
Answer:
sorry
Explanation:
I dont know the anwser to that one
