When the spring is extended by 44.5 cm - 34.0 cm = 10.5 cm = 0.105 m, it exerts a restoring force with magnitude R such that the net force on the mass is
∑ F = R - mg = 0
where mg = weight of the mass = (7.00 kg) g = 68.6 N.
It follows that R = 68.6 N, and by Hooke's law, the spring constant is k such that
k (0.105 m) = 68.6 N ⇒ k = (68.6 N) / (0.105 m) ≈ 653 N/m
9.8 ms^-2 is acceleration
Answer:
Both of them reach the lake at the same time.
Explanation:
We have equation of motion s = ut + 0.5at²
Vertical motion of James : -
Initial velocity, u = 0 m/s
Acceleration, a = g
Displacement, s = h
Substituting,
s = ut + 0.5 at²
h = 0 x t + 0.5 x g x t²
Vertical motion of John : -
Initial velocity, u = 0 m/s
Acceleration, a = g
Displacement, s = h
Substituting,
s = ut + 0.5 at²
h = 0 x t + 0.5 x g x t²
So both times are same.
Both of them reach the lake at the same time.
Answer:
6200 J
Explanation:
Momentum is conserved.
m₁ u₁ + m₂ u₂ = m₁ v₁ + m₂ v₂
The car is initially stationary. The truck and car stick together after the collision, so they have the same final velocity. Therefore:
m₁ u₁ = (m₁ + m₂) v
Solving for the truck's initial velocity:
(2700 kg) u = (2700 kg + 1000 kg) (3 m/s)
u = 4.11 m/s
The change in kinetic energy is therefore:
ΔKE = ½ (m₁ + m₂) v² − ½ m₁ u²
ΔKE = ½ (2700 kg + 1000 kg) (3 m/s)² − ½ (2700 kg) (4.11 m/s)²
ΔKE = -6200 J
6200 J of kinetic energy is "lost".
Answer:
Hope it helps
Explanation:
The higher the bird flies, the bigger the shadow it casts, however, for the shadow to be visible enough the plane or bird would have to be close to the line directly from the sun.
