Answer:
13,750 N
Yes
Explanation:
Given:
v₀ = 90 km/h = 25 m/s
v = 0 m/s
t = 4 s
Find: a and Δx
a = Δv / Δt
a = (0 m/s − 25 m/s) / (4 s)
a = -6.25 m/s²
F = ma
F = (2200 kg) (-6.25 m/s²)
F = -13,750 N
Δx = ½ (v + v₀) t
Δx = ½ (0 m/s + 25 m/s) (4 s)
Δx = 50 m
Answer:
10s
Explanation:
If it took Beatrice 25 seconds to complete the race
Distance = 100 meter
Beatrice speed = 100/25
= 4m/s
If Alice runs at a constant speed and crosses the finish line $5$ seconds, she must have completed the race in 20s (25 -5).
Her speed where constant
= 100/20
= 5 m/s
It would take Alice
= 50/5
= 10s
It would take Alice 10s to run $50$ meters.
Answer:
58.44 C
Explanation:
Electric field is found by
Therefore, the charge is
Therefore, required charge is 58.44 C
Answer:
B. The number of electrons emitted from the metal per second increases.
Explanation:
Light consists of photons . Energy of each photon depends upon frequency of light . The increase in intensity increases the number of photons . It does not increase energy of photons .
So if a high intensity light falls on a photosensitive plate , each photon ejects one electron . So number of electrons increases if we increase intensity of photon. It does not increase kinetic energy of ejected electrons . Work function depends upon the nature of plate.
