# Shawn and his bike have a total mass of 52.8 kg. Shawn rides his bike 0.91 km in 13.1 min at a constant velocity.?

Shawn and his bike have a total mass of

52.8 kg. Shawn rides his bike 0.91 km in

13.1 min at a constant velocity.

The acceleration of gravity is 9.8 m/s

2

.

What is Shawn’s kinetic energy?

### 5 Answers

- MyRankLv 61 month ago
Given,

Mass (m) = 52.8kg

Distance (d) = 0.91km = 0.91 x 10³m

Time (t) = 13.1mins = 786sec

Acceleration due to gravity (g) = 9.81m/sec²

Kinetic Energy (K.E) = ?

We know that:-

Kinetic Energy (K.E) = ½mv² = ½ x 52.8kg x [(0.91 x 10³m) / 786sec]²

= ½ x 52.8 x (1.158)²

= 35.4J

∴ Kinetic Energy (K.E) = 35.4J

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- SpacemanLv 71 month ago
d = distance that Shawn has ridden = 0.91 km = 910 m

t = time that Shawn has ridden = 13.1 min = 786 s

v = velocity = d / t = 1.157760814 m/s

m = combined mass of Shawn and his bike = 52.8 kg

KE = kinetic energy to be determined

KE = 0.5mv²

KE = 0.5(52.8 kg)(1.16 m/s)²

KE = 35.38682672 J ≈ 35.4 J

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- Andrew SmithLv 71 month ago
This is a conversions problem. We know that Ek = 1/2 m v^2

but to get the energy in known units the velocity MUST be in metres per second. v = s/t s = 0.91 km -> 910 m. t= 13.1 min -> 13.1*60s -> v= 910/(13.1*60)

Shawn's bike is a superlightweight bike of 8.2 kg giving HIS mass as 44.6 kg

so Ek Shawn= 1/2 * 44.6 *(910/(13.1*60) )^2 = 29.9 J

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- Anonymous1 month ago
speed = distance / time

convert km/min to m/sec

KE = 1/2 * mass * speed^2

< what do you mean?? >

You need to start paying attention in class or you'll be redoing it. Your choice.

- D3adC3llz1 month agoReport
what do you mean??

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