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Arte-miy333 [17]

3 years ago

6

Matthew is waterskiing. As the boat starts moving, he is at an angle of 8.0° to the right of the boat. The boat applies 250 newt

ons over the first
50 meters, while the angle stays at roughly 8.0°. What work has the boat done on Matthew
A 1.0 x 104 joules
B. 1.2 x 104 joules
C 1.4 x 10^ joules
D. 1.7 x 10^ joules

1 answer:

Citrus2011 [14]3 years ago

5 0

The work done is B. $1.2\cdot 10^4 J$

Explanation:

The work done by a force on an object is given by

$W=Fd cos \theta$

where

F is the magnitude of the force

d is the displacement of the object

$\theta$ is the angle between the direction of the force and of the displacement

For the boat in this problem, we have:

F = 250 N (force applied)

d = 50 m (displacement)

$\theta=8.0^{\circ}$

Substituting, we find the work done:

$W=(250)(50)(cos 8^{\circ})=1.2\cdot 10^4 J$

Learn more about work:

brainly.com/question/6763771

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$| \vec{L}_{rod_i} | = |\vec{r}_i||\vec{p}_i|$

$| \vec{L}_{rod_i} | = r_i * m * v_i$

We know that the distance to the rod is 0.750 m, the mass 2.00 kg and the speed 5 m/s, so:

$| \vec{L}_{rod_i} | = 0.750 \ m \ 2.00 \ kg \ 5 \ \frac{m}{s}$

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$| \vec{L}_{rod_f} | = r_f * m * v_f$

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$| \vec{L}_{rod_f} | = 0.250 m * 2.00 kg * v_f$

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