Ask question

Ask question

All categories

Hunter-Best [27]

4 years ago

15

A skier (down a straight course) is able to enter the starting gate with a speed of 1 m/sec and the average acceleration down th

e hill was 3 m/s2. If
the skier covers the course in 10 sec, how fast was he moving at the bottom of the course?
O31 m
O 13 m/s
O-29 m/s
O 31 m/s

1 answer:

Zigmanuir [339]4 years ago

3 0

He was moving at 31 m/s

You might be interested in

Why do objects in equilibrium have a net force of 0?

lianna [129]

Answer:

Because there is no net force acting o an object in equilibrium.

Explanation:

When object is in equilibrium (either at rest or moving with constant velocity, the net force acting o it is zero.A vector can only have zero magnitude fall of its components are zero this means that all forces acting on the object are balanced.

3 0

3 years ago

A student decides to move a box of books into her dormitory room by pulling on a rope attached to the box. She pulls with a forc

____ [38]

Answer:

Part a)

$a = 0.36 m/s^2$

Part b)

$a = -1.29 m/s^2$

Explanation:

Force applied by the student on the box is 80 N at an angle of 25 degree

so here two components of the force on the box is given as

$F_x = Fcos25$

$F_x = 80 cos25 = 72.5 N$

$F_y = Fsin25$

$F_y = 80 sin25 = 33.8 N$

now in vertical direction we can use force balance for the box to find the normal force on it

$F_n + F_y = mg$

$F_n = (25)(9.81) - 33.8$

$F_n = 211.45 N$

now kinetic friction on the box opposite to applied force due to rough floor is given as

$F_k = \mu F_n$

$F_k = (0.300)(211.45) = 63.44 N$

now the net force on the box in forward direction is given as

$F_{net} = F_x - F_k$

$F_{net} = 72.5 - 63.44 = 9.065 N$

now the acceleration of the box is given as

$a = \frac{F_{net}}{m}$

$a = \frac{9.065}{25} = 0.36 m/s^2$

Part b)

when box is pulled up along the inclined surface of angle 10 degree

now the two components of the force will be same along the inclined and perpendicular to inclined plane

$F_x = 72.5 N$

$F_y = 33.8 N$

now force balance perpendicular to inclined plane is given as

$F_n + F_y = mgcos\theta$

$F_n = (25)(9.81)cos10 - 33.8 = 207.7 N$

now the friction force opposite to the motion on the box is given as

$f_k = \mu F_n$

$f_k = (0.300)(207.7) = 62.3 N$

now the net pulling force along the inclined plane is given as

$F_{net} = F_x - F_k - mgsin10$

$F_{net} = 72.5 - 62.3 - (25)(9.81)sin10$

$F_{net} = -32.38 N$

now the box will decelerate and it is given as

$a = \frac{F_{net}}{m}$

$a = \frac{-32.38}{25} = -1.29 m/s^2$

7 0

3 years ago

A lightning rod effectively protects a building by transferring the electrical current to the ____________.

maria [59]

It transfers the electrical current from the point of contact on the lightning rod into the ground.

6 0

3 years ago

Convert the decimal number 61078 to binary by using sum-of-weights method

marshall27 [118]

Answer:

1110111010010110

Explanation:

I am not able to upload the working out using the sum of weights method sorry

5 0

3 years ago

Through which of the following can magnetic force pass

laiz [17]

All of the above hope this helps :)

8 0

4 years ago

Read 2 more answers