Please help, I don't get this
1 answer:
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Answer:
F = 352 N
Explanation:
we know that:
F*t = ΔP
so:
F*t = M-M
where F is the force excerted by the wall, t is the time, M the mass of the ball, the final velocity of the ball and
the initial velocity.
Replacing values, we get:
F(0.05s) = (0.8 kg)(11m/s)-(0.8 kg)(-11m/s)
solving for F:
F = 352 N
consider east-west direction along X-axis and north-south direction along Y-axis
= velocity of migrating robin relative to air = 12 j m/s
(where "j" is unit vector in Y-direction)
= velocity of air relative to ground = 6.3 i m/s
(where "i" is unit vector in X-direction)
= velocity of migrating robin relative to ground = ?
using the equation
=
+
= 12 j + 6.3 i
= 6.3 i + 12 j
magnitude : sqrt((6.3)² + (12)²) = 13.6 m/s
direction : tan⁻¹(12/6.3) = 62.3 deg north of east
Answer: 4
The mechanical advantage is the ratio of the force exerted by the object to the force applied to do work on it.
Here, Jeff tried to lift a rock weighing 600 pounds by wedging board under the rock. Jeff who weighs 150 pounds uses all his weight to exert force on lever and lift rock.
Mechanical advantage,
Therefore, the mechanical advantage that lever provided to Jeff in lifting rock is 4.