Answer:
93 km/h
Explanation:
Given that a bus took 8 hours to travel 639 km. For the first 5 hours, it travelled at an average speed of 72 km/h
Let the first 5 hours journey distance = F
From the formula of speed,
Speed = distance/time
Substitute speed and time
72 = F/5
F = 72 × 5 = 360 km
The remaining distance will be:
639 - 360 = 279km
The remaining time will be:
8 - 5 = 3 hours
Speed = 279/3
Speed = 93 km/h
Therefore, the average speed for the remaining time of the journey is equal to 93 km/h
Since U=0,
h=1/2gt^2 (h= ut+1/2gt^2, U=0)
h=1/2*10*4*4
h=80m
Answer:
Gravity
Explanation:
Gravity is the force that causes a "disturbance" in space between planets.
Answer:
Explanation:
Impulse of reaction force of floor = change in momentum
Velocity of impact = √ 2gh₁
= √ 2 x 9.8 x 1.5 = 5.4 m /s.
velocity of rebound = √2gh₂
= √ 2x 9.8 x 1
= 4.427 m / s.
Initial momentum = .050 x 5.4 = .27 kg m/s
Final momentum = .05 x 4.427 = .22 kg.m/s
change in momentum = .27 - .22 = .05 kg m/s
Impulse = .05 kg m /s
Impulse = force x time
force = impulse / time
.05 / .015 = 3.33 N.
kinetic energy = 1/2 m v²
Initial kinetic energy = 1/2 x .05 x 5.4²
= 0.729 J
Final Kinetic Energy =1/2 x .05 x 4.427²
= 0.489 J
Change in Kinetic energy =0 .24 J
Lost kinetic energy is due to conversion of energy into sound light etc.
Answer:
N = 23.4 N
Explanation:
After reading that long sentence, let's solve the question
The contact force is the so-called normal in this case we can find it by writing the translational equilibrium equation for the y axis
N - w₁ -w₂ =
N = m₁ g + m₂ g
N = g (m₁ + m₂)
let's calculate
N = 9.8 (0.760 + 1.630)
N = 23.4 N
This is the force of the support of the two blocks on the surface.
