Answer:
-4.5 m/s
Explanation:
Even without doing calculations, we know that a projectile has the same speed coming down as it did going up at the same height. Since it went up at 4.5 m/s, it returns down at -4.5 m/s.
To prove it with math, use the given information:
v₀ = 4.5 m/s
a = -9.8 m/s²
Δy = 0 m
Find: v
v² = v₀² + 2aΔy
v² = (4.5 m/s)² + 2 (-9.8 m/s²) (0 m)
v = -4.5 m/s
Answer: A
Hope this help you!!
Answer is C: Ability to see three-dimensional images of the surfaces of object
Explanation:
To enable the technician see fractures and broken particles in a better resolution as the SEM sees the peaks and valley of the structure.
Relative to the positive horizontal axis, rope 1 makes an angle of 90 + 20 = 110 degrees, while rope 2 makes an angle of 90 - 30 = 60 degrees.
By Newton's second law,
- the net horizontal force acting on the beam is
where 
are the magnitudes of the tensions in ropes 1 and 2, respectively;
- the net vertical force acting on the beam is
where 
and 
.
Eliminating 
, we have
Solve for .
Explanation:
direction of electric field is same as that of force experienced by the test charge
