Answer:
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Explanation:
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Given
The projectile is in air for a time of t=8 sec
To find
The time it takes to reach the highest point
Explanation
A projectile moves up to the highest point and then again moves down following a parabolic path.
So it will reach the highest point at a time half the time it requires to follow teh parabolic path.
The time taken to reach the highest point is 4 sec
Conclusion
The time taken is 4 sec.
Answer:
the charge of the particle is 2.47 x 10⁻¹⁹ C
Explanation:
Given;
mass of the particle, m = 6.64 x 10⁻²⁷ kg
velocity of the particle, v = 8.7 x 10⁵ m/s
strength of the magnetic field, B = 1.3 T
radius of the circle, r = 18 mm = 1.8 x 10⁻³ m
The magnetic force experienced by the charge is calculated as;
F = ma = qvB
where;
q is the charge of the particle
a is the acceleration of the charge in the circular path

Therefore, the charge of the particle is 2.47 x 10⁻¹⁹ C
3.4814815 (or 3 13/27) m/s
speed = distance/time
3.4814815 (or 3 13/27) = 94/27
Answer: Potassium(K)
Explanation:
its an alkali metal placed under sodium and its over rubidium, its also the first element of period 4