Bala temana ye ka šedi gore o tle o akaretše ka mantšu a gago o šeditše dintlhа tše bohlokwa/dikgopolokgolo mabapi le Kamano ya segwera le mogofe, go ya ka ditaelo tše di latelago:

Step 1: Distance traveled after 7 minutes.

Convert time to seconds:

$t = 7 \times 60 = 420~s$

Distance formula for constant acceleration:

$s = ut + \frac{1}{2}at^2$

where $u=10~\mathrm{m/s}$, $a=1~\mathrm{m/s^2}$, $t=420~\mathrm{s}$.

Substitute values:

$s = (10)(420) + \frac{1}{2}(1)(420)^2$

$(420)^2 = 176400$

$s = 4200 + \frac{1}{2}(176400)$

$s = 4200 + 88200$

$s = 92400~m$

92400 m

Step 2: Speed after 7 minutes.

Speed formula:

$v = u + at$

Substitute values:

$v = 10 + (1)(420)$

$v = 10 + 420$

$v = 430~m/s$

430 m/s

Step 3: Time to travel 700 m.

Distance formula:

$s = ut + \frac{1}{2}at^2$

$700 = (10)t + \frac{1}{2}(1)t^2$

$\frac{1}{2}t^2 + 10t - 700 = 0$

Multiply by 2:

$t^2 + 20t - 1400 = 0$

Quadratic formula: $t = \frac{ -20 \pm \sqrt{20^2 - 4(1)(-1400)} }{2}$

Discriminant:

$400 + 5600 = 6000$

$\sqrt{6000} = \sqrt{400 \times 15} = 20\sqrt{15}$

Positive root:

$t = \frac{ -20 + 20\sqrt{15} }{2} = -10 + 10\sqrt{15}~s$

-10 + 10\sqrt{15 s}

Step 4: Speed when distance is 700 m.

Speed formula:

$v^2 = u^2 + 2as$

$v^2 = (10)^2 + 2(1)(700)$

$v^2 = 100 + 1400$

$v^2 = 1500$

$v = \sqrt{1500} = \sqrt{100 \times 15} = 10\sqrt{15}~m/s$

10\sqrt{15 m/s}

Step 5: Average speed for 860 m.

First, final speed $v$ at $s=860~\mathrm{m}$:

$v^2 = u^2 + 2as$

$v^2 = 10^2 + 2(1)(860)$

$v^2 = 100 + 1720$

$v^2 = 1820$

$v = \sqrt{1820} = \sqrt{4 \times 455} = 2\sqrt{455}~m/s$

Average speed:

$v_avg = \frac{u + v}{2}$

$v_avg = \frac{10 + 2\sqrt{455}}{2}$

$v_avg = 5 + \sqrt{455}~m/s$

5 + \sqrt{455 m/s}