Answer:
2.26 s
Explanation:
Let's take down to be positive.
Given (in the y direction):
Δy = 25 m
v₀ = 0 m/s
a = 9.8 m/s²
Find: t
Δy = v₀ t + ½ at²
25 m = (0 m/s) t + ½ (9.8 m/s²) t²
25 = 4.9t²
t = 2.26 s
If the ball instead had an initial horizontal velocity of 5 m/s, its initial vertical velocity is still 0 m/s. So the time to fall is still 2.26 s.
Answer:
d
Explanation:
This is because momentum is defined as p = mv
delta p = Force *time
neither velocity nor time is given so a conclusion cannot be made on which has the greatest momentum change.
Answer:
Explanation:
The sandpaper block did not move because the forces of friction and gravity were balanced.
Answer:
proportional to the current in the wire and inversely proportional to the distance from the wire.
Explanation:
The magnetic field produced by a long, straight current-carrying wire is given by:

where
is the vacuum permeability
I is the current intensity in the wire
r is the distance from the wire
From the formula, we notice that:
- The magnitude of the magnetic field is directly proportional to I, the current
- The magnitude of the magnetic field is inversely proportional to the distance from the wire, r
Therefore, correct option is
proportional to the current in the wire and inversely proportional to the distance from the wire.