Answer:
U = 30 m/s
a = 3 m/s²
Explanation:
"A car accelerating uniformly from rest reaches a maximum speed of U in 10 s. It then moves with that speed for an additional 20 s. The distance covered by the car in the 30 s interval is 750 m. Find U and the acceleration of the car in the first 10 s."
During the first 10 s:
v₀ = 0 m/s
v = U m/s
t = 10 s
The distance covered in this time is the average velocity times time:
Δx = ½ (v + v₀) t
Δx = ½ (U + 0) (10)
Δx = 5U
The distance covered in the next 20 seconds is speed times time:
Δx = 20U
The total distance is 750 m:
5U + 20U = 750
25U = 750
U = 30 m/s
The acceleration during the first 10 seconds is the change in speed over change in time.
a = Δv / Δt
a = (30 m/s − 0 m/s) / 10 s
a = 3 m/s²
The correct answer I think would be B
Answer:
yes, should be
Explanation:
This is a hard yes or no question becuase the amplitudes are the same height but in different beating orders.
Answer:
77.3J
Explanation:
Given parameters:
Mass of the bullet = 50g = 0.05kg
Velocity of the bullet = 200km/hr
Unknown:
Kinetic energy of the bullet = ?
Solution:
Kinetic energy is the energy due to motion of a body.
It is mathematically expressed as;
K.E = 
m v²
m is the mass
v is the velocity
we need to convert the velocity to m/s
200km/hr is 55.6m/s
Input the parameters and solve;
K.E = x 0.05 x 55.6² = 77.3J
Momentum = (mass) x (speed)
Momentum = (8 kg) x (5 m/s)
Momentum = 40 kg-m/s
