Mechanics | Relativity Answers

Leo who has a mass of 70 kg stretches

the trampoline mat by 37 cm. Calculate the

elastic potential energy he puts into the

trampoline mat.

a body requires a force of 100N to accelerate it at a rate of 0.2m/s^2. determine the mass of the body in kilograms and in slugs

An object with an initial velocity of 20 m/s accelerates uniformly at 5 m/s 2 in the direction of its motion at a distance of 10 m. What is the final velocity of the object?

In a 300-m race, runner A starts from rests and accelerates at 1.6m/s2

for the first 30 m and then runs

at a constant speed. Runner B starts from rests and accelerates at 2.0m/s2

for the first 30m and then

runs at a constant speed. Runner A begins running as soon as the race begins but B firsts takes a nap

to rest up. What is the longest nap that B can take and still not to lose the race?

So how would you calculate the force of F needed to keep the engine stationary by first resolving the forces into their horizontal and vertical components.

A car traveling at constant velocity of 20m/s passes a stationary police car and 15 seconds later the police car accelerates uniformly at 4m/s to reach a speed of 30m/s with which it continues. a) draw a velocity time graph. b) find where the second car overtakes the first car. c) find the distance up to which the second car overtakes the first car

A train starts from a station at point A and accelerates uniformly to a speed of 20m/s. It maintains this speed and then retards uniformly until it comes to rest at point B. The distance between the stations is 2000m the total time taken is 2 minutes.if the acceleration is twice the retardation. a) draw a velocity time graph. b) find the time for which the train is moving at constant speed. c) find it's retardation

Jamylla and Janylla are on a hike. Both hikers begin a trip by walking, the first leg A: 2.65 km, 140° from their base

camp, on their second leg B: 4.77 km, 252° and to complete their final leg C: 3.18 km, 332°. What is the magnitude and

direction of their final position from their base camp? Apply polygon method and component method and compare their

results.

Given: A = 100m, 30°NofE; B⃑ = 80m, 30°WofNandC = 40m, 55°SofW

a) Write each vector in Figure on the right in terms of

the unit vectors î and ĵ.

b) Use unit vectors to express the vector C , where

C = 3.0A − 4.0B⃑ .

c) Find the magnitude and direction of C .

Given: A = 100m, 30°NofE; B⃑ = 80m, 30°WofNandC = 40m, 55°SofW

a. Plot the given vectors in the coordinate plane.

b. Calculate the components of vectors A, B and C.

c. Write each vector in terms of the unit vectors.

d. Determine the resultant vector.