Answer:
The angle is
Explanation:
From the question we are told that
The distance of the dartboard from the dart is
The time taken is
The horizontal component of the speed of the dart is mathematically represented as
where u is the the velocity at dart is lunched
so
substituting values
=>
From projectile kinematics the time taken by the dart can be mathematically represented as
=>
=>
Answer:
The angle of incidence when the reflected ray is perpendicular to the incident ray = 45°
Explanation:
According to Snell's Law,
n₁ sin θ₁ = n₂ sin θ₂
When the angle between the incident ray and reflected ray is 90°, the angle of incidence is θ₁ and the angle of reflection, θ₂ = 90° - θ₁ and the index of refraction in the Snell's Law for both media would be the same, n₁ = n₂ = n
n sin θ₁ = n sin (90° - θ₁)
Note that from trigonometric relations,
Sin (90° - θ₁) = cos θ₁
n sin θ₁ = n cos θ₁
(sin θ₁)/(cos θ₁) = 1
tan θ₁ = 1
θ₁ = arctan 1 = 45°
Hope this Helps!!!
Answer:
option A
Explanation:
given,
For exerted by the worker = 245 N
angle made with horizontal = 55°
we need to calculate Force which is not used to move the crate = ?
Movement of crate is due to the horizontal component of the force.
Crate will not move due to vertical force acting on the it.
hence, worker's force not used to move the crate is equal to 200.69
The correct answer is option A