When hockey players push the puck along the ice it slides causing heat which melts the ice causing the friction against the ice to be less.
Answer:
2N
Explanation:
subtract rthe two forces to see which is greater
4-2=2
Answer: 343 m/s. The sound wave has a frequency of. 436 Hz. What is the period of the wave? T = = 436 Hz. = 2.29x10-3 s. C. What is the wave's wavelength? To halve
Explanation:
Answer: When the flashlight is turned on, the chemical energy stored in batteries is converted into electrical energy that flows through wires of flashlight. This electrical energy is then transformed into light and heat energies.
Explanation:
Answer:
K_a = 8,111 J
Explanation:
This is a collision exercise, let's define the system as formed by the two particles A and B, in this way the forces during the collision are internal and the moment is conserved
initial instant. Just before dropping the particles
p₀ = 0
final moment
p_f = m_a v_a + m_b v_b
p₀ = p_f
0 = m_a v_a + m_b v_b
tells us that
m_a = 8 m_b
0 = 8 m_b v_a + m_b v_b
v_b = - 8 v_a (1)
indicate that the transfer is complete, therefore the kinematic energy is conserved
starting point
Em₀ = K₀ = 73 J
final point. After separating the body
Em_f = K_f = ½ m_a v_a² + ½ m_b v_b²
K₀ = K_f
73 = ½ m_a (v_a² + v_b² / 8)
we substitute equation 1
73 = ½ m_a (v_a² + 8² v_a² / 8)
73 = ½ m_a (9 v_a²)
73/9 = ½ m_a (v_a²) = K_a
K_a = 8,111 J
